[ aws . wafv2 ]

get-web-acl

Description

Retrieves the specified WebACL .

See also: AWS API Documentation

See ‘aws help’ for descriptions of global parameters.

Synopsis

  get-web-acl
--name <value>
--scope <value>
--id <value>
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]

Options

--name (string)

The name of the web ACL. You cannot change the name of a web ACL after you create it.

--scope (string)

Specifies whether this is for an Amazon CloudFront distribution or for a regional application. A regional application can be an Application Load Balancer (ALB), an Amazon API Gateway REST API, or an AppSync GraphQL API.

To work with CloudFront, you must also specify the Region US East (N. Virginia) as follows:

  • CLI - Specify the Region when you use the CloudFront scope: --scope=CLOUDFRONT --region=us-east-1 .

  • API and SDKs - For all calls, use the Region endpoint us-east-1.

Possible values:

  • CLOUDFRONT

  • REGIONAL

--id (string)

The unique identifier for the web ACL. This ID is returned in the responses to create and list commands. You provide it to operations like update and delete.

--cli-input-json | --cli-input-yaml (string) Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. Similarly, if provided yaml-input it will print a sample input YAML that can be used with --cli-input-yaml. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See ‘aws help’ for descriptions of global parameters.

Examples

To retrieve a web ACL

The following get-web-acl retrieves the web ACL with the specified name, scope, and ID. You can get the ID for a web ACL from the commands create-web-acl and list-web-acls.

aws wafv2 get-web-acl \
    --name test01 \
    --scope REGIONAL \
    --id a1b2c3d4-5678-90ab-cdef-EXAMPLE11111

Output:

{
    "WebACL":{
        "Capacity":3,
        "Description":"",
        "Rules":[
            {
                "Priority":1,
                "Action":{
                    "Block":{

                    }
                },
                "VisibilityConfig":{
                   "SampledRequestsEnabled":true,
                    "CloudWatchMetricsEnabled":true,
                    "MetricName":"testrule01"
                },
                "Name":"testrule01",
                "Statement":{
                    "AndStatement":{
                        "Statements":[
                            {
                                "ByteMatchStatement":{
                                    "PositionalConstraint":"EXACTLY",
                                    "TextTransformations":[
                                        {
                                            "Priority":0,
                                            "Type":"NONE"
                                        }
                                    ],
                                    "SearchString":"dGVzdHN0cmluZw==",
                                    "FieldToMatch":{
                                        "UriPath":{

                                        }
                                    }
                                }
                            },
                            {
                                "SizeConstraintStatement":{
                                    "ComparisonOperator":"EQ",
                                    "TextTransformations":[
                                        {
                                            "Priority":0,
                                            "Type":"NONE"
                                        }
                                    ],
                                    "FieldToMatch":{
                                        "QueryString":{

                                        }
                                    },
                                    "Size":0
                                }
                            }
                        ]
                    }
                }
            }
        ],
        "VisibilityConfig":{
            "SampledRequestsEnabled":true,
            "CloudWatchMetricsEnabled":true,
            "MetricName":"test01"
        },
        "DefaultAction":{
            "Allow":{

            }
        },
        "Id":"a1b2c3d4-5678-90ab-cdef-EXAMPLE11111",
        "ARN":"arn:aws:wafv2:us-west-2:123456789012:regional/webacl/test01/a1b2c3d4-5678-90ab-cdef-EXAMPLE11111",
        "Name":"test01"
    },
    "LockToken":"e3db7e2c-d58b-4ee6-8346-6aec5511c6fb"
}

For more information, see Managing and Using a Web Access Control List (Web ACL) in the AWS WAF, AWS Firewall Manager, and AWS Shield Advanced Developer Guide.

Output

WebACL -> (structure)

The web ACL specification. You can modify the settings in this web ACL and use it to update this web ACL or create a new one.

Name -> (string)

The name of the web ACL. You cannot change the name of a web ACL after you create it.

Id -> (string)

A unique identifier for the WebACL . This ID is returned in the responses to create and list commands. You use this ID to do things like get, update, and delete a WebACL .

ARN -> (string)

The Amazon Resource Name (ARN) of the web ACL that you want to associate with the resource.

DefaultAction -> (structure)

The action to perform if none of the Rules contained in the WebACL match.

Block -> (structure)

Specifies that WAF should block requests by default.

CustomResponse -> (structure)

Defines a custom response for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

ResponseCode -> (integer)

The HTTP status code to return to the client.

For a list of status codes that you can use in your custom reqponses, see Supported status codes for custom response in the WAF Developer Guide .

CustomResponseBodyKey -> (string)

References the response body that you want WAF to return to the web request client. You can define a custom response for a rule action or a default web ACL action that is set to block. To do this, you first define the response body key and value in the CustomResponseBodies setting for the WebACL or RuleGroup where you want to use it. Then, in the rule action or web ACL default action BlockAction setting, you reference the response body using this key.

ResponseHeaders -> (list)

The HTTP headers to use in the response. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

Allow -> (structure)

Specifies that WAF should allow requests by default.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

Description -> (string)

A description of the web ACL that helps with identification.

Rules -> (list)

The Rule statements used to identify the web requests that you want to allow, block, or count. Each rule includes one top-level statement that WAF uses to identify matching web requests, and parameters that govern how WAF handles them.

(structure)

A single rule, which you can use in a WebACL or RuleGroup to identify web requests that you want to allow, block, or count. Each rule includes one top-level Statement that WAF uses to identify matching web requests, and parameters that govern how WAF handles them.

Name -> (string)

The name of the rule. You can’t change the name of a Rule after you create it.

Priority -> (integer)

If you define more than one Rule in a WebACL , WAF evaluates each request against the Rules in order based on the value of Priority . WAF processes rules with lower priority first. The priorities don’t need to be consecutive, but they must all be different.

Statement -> (structure)

The WAF processing statement for the rule, for example ByteMatchStatement or SizeConstraintStatement .

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the rate-based statement. Requests are only tracked by the rate-based statement if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

Statement -> (structure)

The statement to negate. You can use any statement that can be nested.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the managed rule group. Requests are only evaluated by the rule group if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

Action -> (structure)

The action that WAF should take on a web request when it matches the rule statement. Settings at the web ACL level can override the rule action setting.

This is used only for rules whose statements do not reference a rule group. Rule statements that reference a rule group include RuleGroupReferenceStatement and ManagedRuleGroupStatement .

You must specify either this Action setting or the rule OverrideAction setting, but not both:

  • If the rule statement does not reference a rule group, use this rule action setting and not the rule override action setting.

  • If the rule statement references a rule group, use the override action setting and not this action setting.

Block -> (structure)

Instructs WAF to block the web request.

CustomResponse -> (structure)

Defines a custom response for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

ResponseCode -> (integer)

The HTTP status code to return to the client.

For a list of status codes that you can use in your custom reqponses, see Supported status codes for custom response in the WAF Developer Guide .

CustomResponseBodyKey -> (string)

References the response body that you want WAF to return to the web request client. You can define a custom response for a rule action or a default web ACL action that is set to block. To do this, you first define the response body key and value in the CustomResponseBodies setting for the WebACL or RuleGroup where you want to use it. Then, in the rule action or web ACL default action BlockAction setting, you reference the response body using this key.

ResponseHeaders -> (list)

The HTTP headers to use in the response. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

Allow -> (structure)

Instructs WAF to allow the web request.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

Count -> (structure)

Instructs WAF to count the web request and allow it.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

Captcha -> (structure)

Instructs WAF to run a CAPTCHA check against the web request.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

OverrideAction -> (structure)

The action to use in the place of the action that results from the rule group evaluation. Set the override action to none to leave the result of the rule group alone. Set it to count to override the result to count only.

You can only use this for rule statements that reference a rule group, like RuleGroupReferenceStatement and ManagedRuleGroupStatement .

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

Count -> (structure)

Override the rule group evaluation result to count only.

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

None -> (structure)

Don’t override the rule group evaluation result. This is the most common setting.

RuleLabels -> (list)

Labels to apply to web requests that match the rule match statement. WAF applies fully qualified labels to matching web requests. A fully qualified label is the concatenation of a label namespace and a rule label. The rule’s rule group or web ACL defines the label namespace.

Rules that run after this rule in the web ACL can match against these labels using a LabelMatchStatement .

For each label, provide a case-sensitive string containing optional namespaces and a label name, according to the following guidelines:

  • Separate each component of the label with a colon.

  • Each namespace or name can have up to 128 characters.

  • You can specify up to 5 namespaces in a label.

  • Don’t use the following reserved words in your label specification: aws , waf , managed , rulegroup , webacl , regexpatternset , or ipset .

For example, myLabelName or nameSpace1:nameSpace2:myLabelName .

(structure)

A single label container. This is used as an element of a label array in multiple contexts, for example, in RuleLabels inside a Rule and in Labels inside a SampledHTTPRequest .

Name -> (string)

The label string.

VisibilityConfig -> (structure)

Defines and enables Amazon CloudWatch metrics and web request sample collection.

SampledRequestsEnabled -> (boolean)

A boolean indicating whether WAF should store a sampling of the web requests that match the rules. You can view the sampled requests through the WAF console.

CloudWatchMetricsEnabled -> (boolean)

A boolean indicating whether the associated resource sends metrics to Amazon CloudWatch. For the list of available metrics, see WAF Metrics .

MetricName -> (string)

A name of the Amazon CloudWatch metric. The name can contain only the characters: A-Z, a-z, 0-9, - (hyphen), and _ (underscore). The name can be from one to 128 characters long. It can’t contain whitespace or metric names reserved for WAF, for example “All” and “Default_Action.”

CaptchaConfig -> (structure)

Specifies how WAF should handle CAPTCHA evaluations. If you don’t specify this, WAF uses the CAPTCHA configuration that’s defined for the web ACL.

ImmunityTimeProperty -> (structure)

Determines how long a CAPTCHA token remains valid after the client successfully solves a CAPTCHA puzzle.

ImmunityTime -> (long)

The amount of time, in seconds, that a CAPTCHA token is valid. The default setting is 300.

VisibilityConfig -> (structure)

Defines and enables Amazon CloudWatch metrics and web request sample collection.

SampledRequestsEnabled -> (boolean)

A boolean indicating whether WAF should store a sampling of the web requests that match the rules. You can view the sampled requests through the WAF console.

CloudWatchMetricsEnabled -> (boolean)

A boolean indicating whether the associated resource sends metrics to Amazon CloudWatch. For the list of available metrics, see WAF Metrics .

MetricName -> (string)

A name of the Amazon CloudWatch metric. The name can contain only the characters: A-Z, a-z, 0-9, - (hyphen), and _ (underscore). The name can be from one to 128 characters long. It can’t contain whitespace or metric names reserved for WAF, for example “All” and “Default_Action.”

Capacity -> (long)

The web ACL capacity units (WCUs) currently being used by this web ACL.

WAF uses WCUs to calculate and control the operating resources that are used to run your rules, rule groups, and web ACLs. WAF calculates capacity differently for each rule type, to reflect the relative cost of each rule. Simple rules that cost little to run use fewer WCUs than more complex rules that use more processing power. Rule group capacity is fixed at creation, which helps users plan their web ACL WCU usage when they use a rule group. The WCU limit for web ACLs is 1,500.

PreProcessFirewallManagerRuleGroups -> (list)

The first set of rules for WAF to process in the web ACL. This is defined in an Firewall Manager WAF policy and contains only rule group references. You can’t alter these. Any rules and rule groups that you define for the web ACL are prioritized after these.

In the Firewall Manager WAF policy, the Firewall Manager administrator can define a set of rule groups to run first in the web ACL and a set of rule groups to run last. Within each set, the administrator prioritizes the rule groups, to determine their relative processing order.

(structure)

A rule group that’s defined for an Firewall Manager WAF policy.

Name -> (string)

The name of the rule group. You cannot change the name of a rule group after you create it.

Priority -> (integer)

If you define more than one rule group in the first or last Firewall Manager rule groups, WAF evaluates each request against the rule groups in order, starting from the lowest priority setting. The priorities don’t need to be consecutive, but they must all be different.

FirewallManagerStatement -> (structure)

The processing guidance for an Firewall Manager rule. This is like a regular rule Statement , but it can only contain a rule group reference.

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the managed rule group. Requests are only evaluated by the rule group if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the rate-based statement. Requests are only tracked by the rate-based statement if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

Statement -> (structure)

The statement to negate. You can use any statement that can be nested.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the managed rule group. Requests are only evaluated by the rule group if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

( … recursive … )LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

OverrideAction -> (structure)

The action to use in the place of the action that results from the rule group evaluation. Set the override action to none to leave the result of the rule group alone. Set it to count to override the result to count only.

You can only use this for rule statements that reference a rule group, like RuleGroupReferenceStatement and ManagedRuleGroupStatement .

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

Count -> (structure)

Override the rule group evaluation result to count only.

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

None -> (structure)

Don’t override the rule group evaluation result. This is the most common setting.

VisibilityConfig -> (structure)

Defines and enables Amazon CloudWatch metrics and web request sample collection.

SampledRequestsEnabled -> (boolean)

A boolean indicating whether WAF should store a sampling of the web requests that match the rules. You can view the sampled requests through the WAF console.

CloudWatchMetricsEnabled -> (boolean)

A boolean indicating whether the associated resource sends metrics to Amazon CloudWatch. For the list of available metrics, see WAF Metrics .

MetricName -> (string)

A name of the Amazon CloudWatch metric. The name can contain only the characters: A-Z, a-z, 0-9, - (hyphen), and _ (underscore). The name can be from one to 128 characters long. It can’t contain whitespace or metric names reserved for WAF, for example “All” and “Default_Action.”

PostProcessFirewallManagerRuleGroups -> (list)

The last set of rules for WAF to process in the web ACL. This is defined in an Firewall Manager WAF policy and contains only rule group references. You can’t alter these. Any rules and rule groups that you define for the web ACL are prioritized before these.

In the Firewall Manager WAF policy, the Firewall Manager administrator can define a set of rule groups to run first in the web ACL and a set of rule groups to run last. Within each set, the administrator prioritizes the rule groups, to determine their relative processing order.

(structure)

A rule group that’s defined for an Firewall Manager WAF policy.

Name -> (string)

The name of the rule group. You cannot change the name of a rule group after you create it.

Priority -> (integer)

If you define more than one rule group in the first or last Firewall Manager rule groups, WAF evaluates each request against the rule groups in order, starting from the lowest priority setting. The priorities don’t need to be consecutive, but they must all be different.

FirewallManagerStatement -> (structure)

The processing guidance for an Firewall Manager rule. This is like a regular rule Statement , but it can only contain a rule group reference.

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the managed rule group. Requests are only evaluated by the rule group if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the rate-based statement. Requests are only tracked by the rate-based statement if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

(structure)

The processing guidance for a Rule , used by WAF to determine whether a web request matches the rule.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

Statement -> (structure)

The statement to negate. You can use any statement that can be nested.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

( … recursive … )ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupStatement -> (structure)

A rule statement used to run the rules that are defined in a managed rule group. To use this, provide the vendor name and the name of the rule group in this statement. You can retrieve the required names by calling ListAvailableManagedRuleGroups .

You cannot nest a ManagedRuleGroupStatement , for example for use inside a NotStatement or OrStatement . It can only be referenced as a top-level statement within a rule.

VendorName -> (string)

The name of the managed rule group vendor. You use this, along with the rule group name, to identify the rule group.

Name -> (string)

The name of the managed rule group. You use this, along with the vendor name, to identify the rule group.

Version -> (string)

The version of the managed rule group to use. If you specify this, the version setting is fixed until you change it. If you don’t specify this, WAF uses the vendor’s default version, and then keeps the version at the vendor’s default when the vendor updates the managed rule group settings.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

ScopeDownStatement -> (structure)

An optional nested statement that narrows the scope of the web requests that are evaluated by the managed rule group. Requests are only evaluated by the rule group if they match the scope-down statement. You can use any nestable Statement in the scope-down statement, and you can nest statements at any level, the same as you can for a rule statement.

ByteMatchStatement -> (structure)

A rule statement that defines a string match search for WAF to apply to web requests. The byte match statement provides the bytes to search for, the location in requests that you want WAF to search, and other settings. The bytes to search for are typically a string that corresponds with ASCII characters. In the WAF console and the developer guide, this is refered to as a string match statement.

SearchString -> (blob)

A string value that you want WAF to search for. WAF searches only in the part of web requests that you designate for inspection in FieldToMatch . The maximum length of the value is 50 bytes.

Valid values depend on the component that you specify for inspection in FieldToMatch :

  • Method : The HTTP method that you want WAF to search for. This indicates the type of operation specified in the request.

  • UriPath : The value that you want WAF to search for in the URI path, for example, /images/daily-ad.jpg .

If SearchString includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

If you’re using the WAF API

Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

For example, suppose the value of Type is HEADER and the value of Data is User-Agent . If you want to search the User-Agent header for the value BadBot , you base64-encode BadBot using MIME base64-encoding and include the resulting value, QmFkQm90 , in the value of SearchString .

If you’re using the CLI or one of the Amazon Web Services SDKs

The value that you want WAF to search for. The SDK automatically base64 encodes the value.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

PositionalConstraint -> (string)

The area within the portion of the web request that you want WAF to search for SearchString . Valid values include the following:

CONTAINS

The specified part of the web request must include the value of SearchString , but the location doesn’t matter.

CONTAINS_WORD

The specified part of the web request must include the value of SearchString , and SearchString must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, SearchString must be a word, which means that both of the following are true:

  • SearchString is at the beginning of the specified part of the web request or is preceded by a character other than an alphanumeric character or underscore (_). Examples include the value of a header and ;BadBot .

  • SearchString is at the end of the specified part of the web request or is followed by a character other than an alphanumeric character or underscore (_), for example, BadBot; and -BadBot; .

EXACTLY

The value of the specified part of the web request must exactly match the value of SearchString .

STARTS_WITH

The value of SearchString must appear at the beginning of the specified part of the web request.

ENDS_WITH

The value of SearchString must appear at the end of the specified part of the web request.

SqliMatchStatement -> (structure)

Attackers sometimes insert malicious SQL code into web requests in an effort to extract data from your database. To allow or block web requests that appear to contain malicious SQL code, create one or more SQL injection match conditions. An SQL injection match condition identifies the part of web requests, such as the URI or the query string, that you want WAF to inspect. Later in the process, when you create a web ACL, you specify whether to allow or block requests that appear to contain malicious SQL code.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

XssMatchStatement -> (structure)

A rule statement that defines a cross-site scripting (XSS) match search for WAF to apply to web requests. XSS attacks are those where the attacker uses vulnerabilities in a benign website as a vehicle to inject malicious client-site scripts into other legitimate web browsers. The XSS match statement provides the location in requests that you want WAF to search and text transformations to use on the search area before WAF searches for character sequences that are likely to be malicious strings.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

SizeConstraintStatement -> (structure)

A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure WAF to inspect the request body, WAF inspects only the first 8192 bytes (8 KB). If the request body for your web requests never exceeds 8192 bytes, you can create a size constraint condition and block requests that have a request body greater than 8192 bytes.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

ComparisonOperator -> (string)

The operator to use to compare the request part to the size setting.

Size -> (long)

The size, in byte, to compare to the request part, after any transformations.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

GeoMatchStatement -> (structure)

A rule statement used to identify web requests based on country of origin.

CountryCodes -> (list)

An array of two-character country codes, for example, [ "US", "CN" ] , from the alpha-2 country ISO codes of the ISO 3166 international standard.

(string)

ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

IPSetReferenceStatement -> (structure)

A rule statement used to detect web requests coming from particular IP addresses or address ranges. To use this, create an IPSet that specifies the addresses you want to detect, then use the ARN of that set in this statement. To create an IP set, see CreateIPSet .

Each IP set rule statement references an IP set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the IPSet that this statement references.

IPSetForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Position -> (string)

The position in the header to search for the IP address. The header can contain IP addresses of the original client and also of proxies. For example, the header value could be 10.1.1.1, 127.0.0.0, 10.10.10.10 where the first IP address identifies the original client and the rest identify proxies that the request went through.

The options for this setting are the following:

  • FIRST - Inspect the first IP address in the list of IP addresses in the header. This is usually the client’s original IP.

  • LAST - Inspect the last IP address in the list of IP addresses in the header.

  • ANY - Inspect all IP addresses in the header for a match. If the header contains more than 10 IP addresses, WAF inspects the last 10.

RegexPatternSetReferenceStatement -> (structure)

A rule statement used to search web request components for matches with regular expressions. To use this, create a RegexPatternSet that specifies the expressions that you want to detect, then use the ARN of that set in this statement. A web request matches the pattern set rule statement if the request component matches any of the patterns in the set. To create a regex pattern set, see CreateRegexPatternSet .

Each regex pattern set rule statement references a regex pattern set. You create and maintain the set independent of your rules. This allows you to use the single set in multiple rules. When you update the referenced set, WAF automatically updates all rules that reference it.

ARN -> (string)

The Amazon Resource Name (ARN) of the RegexPatternSet that this statement references.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

RateBasedStatement -> (structure)

A rate-based rule tracks the rate of requests for each originating IP address, and triggers the rule action when the rate exceeds a limit that you specify on the number of requests in any 5-minute time span. You can use this to put a temporary block on requests from an IP address that is sending excessive requests.

WAF tracks and manages web requests separately for each instance of a rate-based rule that you use. For example, if you provide the same rate-based rule settings in two web ACLs, each of the two rule statements represents a separate instance of the rate-based rule and gets its own tracking and management by WAF. If you define a rate-based rule inside a rule group, and then use that rule group in multiple places, each use creates a separate instance of the rate-based rule that gets its own tracking and management by WAF.

When the rule action triggers, WAF blocks additional requests from the IP address until the request rate falls below the limit.

You can optionally nest another statement inside the rate-based statement, to narrow the scope of the rule so that it only counts requests that match the nested statement. For example, based on recent requests that you have seen from an attacker, you might create a rate-based rule with a nested AND rule statement that contains the following nested statements:

  • An IP match statement with an IP set that specified the address 192.0.2.44.

  • A string match statement that searches in the User-Agent header for the string BadBot.

In this rate-based rule, you also define a rate limit. For this example, the rate limit is 1,000. Requests that meet both of the conditions in the statements are counted. If the count exceeds 1,000 requests per five minutes, the rule action triggers. Requests that do not meet both conditions are not counted towards the rate limit and are not affected by this rule.

You cannot nest a RateBasedStatement inside another statement, for example inside a NotStatement or OrStatement . You can define a RateBasedStatement inside a web ACL and inside a rule group.

Limit -> (long)

The limit on requests per 5-minute period for a single originating IP address. If the statement includes a ScopeDownStatement , this limit is applied only to the requests that match the statement.

AggregateKeyType -> (string)

Setting that indicates how to aggregate the request counts. The options are the following:

  • IP - Aggregate the request counts on the IP address from the web request origin.

  • FORWARDED_IP - Aggregate the request counts on the first IP address in an HTTP header. If you use this, configure the ForwardedIPConfig , to specify the header to use.

( … recursive … )ForwardedIPConfig -> (structure)

The configuration for inspecting IP addresses in an HTTP header that you specify, instead of using the IP address that’s reported by the web request origin. Commonly, this is the X-Forwarded-For (XFF) header, but you can specify any header name.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

This is required if AggregateKeyType is set to FORWARDED_IP .

HeaderName -> (string)

The name of the HTTP header to use for the IP address. For example, to use the X-Forwarded-For (XFF) header, set this to X-Forwarded-For .

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

FallbackBehavior -> (string)

The match status to assign to the web request if the request doesn’t have a valid IP address in the specified position.

Note

If the specified header isn’t present in the request, WAF doesn’t apply the rule to the web request at all.

You can specify the following fallback behaviors:

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

AndStatement -> (structure)

A logical rule statement used to combine other rule statements with AND logic. You provide more than one Statement within the AndStatement .

Statements -> (list)

The statements to combine with AND logic. You can use any statements that can be nested.

( … recursive … )

OrStatement -> (structure)

A logical rule statement used to combine other rule statements with OR logic. You provide more than one Statement within the OrStatement .

Statements -> (list)

The statements to combine with OR logic. You can use any statements that can be nested.

( … recursive … )

NotStatement -> (structure)

A logical rule statement used to negate the results of another rule statement. You provide one Statement within the NotStatement .

( … recursive … )

( … recursive … )LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

LabelMatchStatement -> (structure)

A rule statement that defines a string match search against labels that have been added to the web request by rules that have already run in the web ACL.

The label match statement provides the label or namespace string to search for. The label string can represent a part or all of the fully qualified label name that had been added to the web request. Fully qualified labels have a prefix, optional namespaces, and label name. The prefix identifies the rule group or web ACL context of the rule that added the label. If you do not provide the fully qualified name in your label match string, WAF performs the search for labels that were added in the same context as the label match statement.

Scope -> (string)

Specify whether you want to match using the label name or just the namespace.

Key -> (string)

The string to match against. The setting you provide for this depends on the match statement’s Scope setting:

  • If the Scope indicates LABEL , then this specification must include the name and can include any number of preceding namespace specifications and prefix up to providing the fully qualified label name.

  • If the Scope indicates NAMESPACE , then this specification can include any number of contiguous namespace strings, and can include the entire label namespace prefix from the rule group or web ACL where the label originates.

Labels are case sensitive and components of a label must be separated by colon, for example NS1:NS2:name .

RegexMatchStatement -> (structure)

A rule statement used to search web request components for a match against a single regular expression.

RegexString -> (string)

The string representing the regular expression.

FieldToMatch -> (structure)

The part of the web request that you want WAF to inspect. For more information, see FieldToMatch .

SingleHeader -> (structure)

Inspect a single header. Provide the name of the header to inspect, for example, User-Agent or Referer . This setting isn’t case sensitive.

Example JSON: "SingleHeader": { "Name": "haystack" }

Alternately, you can filter and inspect all headers with the Headers FieldToMatch setting.

Name -> (string)

The name of the query header to inspect.

SingleQueryArgument -> (structure)

Inspect a single query argument. Provide the name of the query argument to inspect, such as UserName or SalesRegion . The name can be up to 30 characters long and isn’t case sensitive.

Example JSON: "SingleQueryArgument": { "Name": "myArgument" }

Name -> (string)

The name of the query argument to inspect.

AllQueryArguments -> (structure)

Inspect all query arguments.

UriPath -> (structure)

Inspect the request URI path. This is the part of the web request that identifies a resource, for example, /images/daily-ad.jpg .

QueryString -> (structure)

Inspect the query string. This is the part of a URL that appears after a ? character, if any.

Body -> (structure)

Inspect the request body as plain text. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the Body object configuration.

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Method -> (structure)

Inspect the HTTP method. The method indicates the type of operation that the request is asking the origin to perform.

JsonBody -> (structure)

Inspect the request body as JSON. The request body immediately follows the request headers. This is the part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form.

Only the first 8 KB (8192 bytes) of the request body are forwarded to WAF for inspection by the underlying host service. For information about how to handle oversized request bodies, see the JsonBody object configuration.

MatchPattern -> (structure)

The patterns to look for in the JSON body. WAF inspects the results of these pattern matches against the rule inspection criteria.

All -> (structure)

Match all of the elements. See also MatchScope in JsonBody .

You must specify either this setting or the IncludedPaths setting, but not both.

IncludedPaths -> (list)

Match only the specified include paths. See also MatchScope in JsonBody .

Provide the include paths using JSON Pointer syntax. For example, "IncludedPaths": ["/dogs/0/name", "/dogs/1/name"] . For information about this syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer .

You must specify either this setting or the All setting, but not both.

Note

Don’t use this option to include all paths. Instead, use the All setting.

(string)

MatchScope -> (string)

The parts of the JSON to match against using the MatchPattern . If you specify All , WAF matches against keys and values.

InvalidFallbackBehavior -> (string)

What WAF should do if it fails to completely parse the JSON body. The options are the following:

  • EVALUATE_AS_STRING - Inspect the body as plain text. WAF applies the text transformations and inspection criteria that you defined for the JSON inspection to the body text string.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

If you don’t provide this setting, WAF parses and evaluates the content only up to the first parsing failure that it encounters.

WAF does its best to parse the entire JSON body, but might be forced to stop for reasons such as invalid characters, duplicate keys, truncation, and any content whose root node isn’t an object or an array.

WAF parses the JSON in the following examples as two valid key, value pairs:

  • Missing comma: {"key1":"value1""key2":"value2"}

  • Missing colon: {"key1":"value1","key2""value2"}

  • Extra colons: {"key1"::"value1","key2""value2"}

OversizeHandling -> (string)

What WAF should do if the body is larger than WAF can inspect. WAF does not support inspecting the entire contents of the body of a web request when the body exceeds 8 KB (8192 bytes). Only the first 8 KB of the request body are forwarded to WAF by the underlying host service.

The options for oversize handling are the following:

  • CONTINUE - Inspect the body normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

You can combine the MATCH or NO_MATCH settings for oversize handling with your rule and web ACL action settings, so that you block any request whose body is over 8 KB.

Default: CONTINUE

Headers -> (structure)

Inspect the request headers. You must configure scope and pattern matching filters in the Headers object, to define the set of headers to and the parts of the headers that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s headers and only the first 200 headers are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize header content in the Headers object. WAF applies the pattern matching filters to the headers that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of headers to inspect in a web request.

You must specify exactly one setting: either All , IncludedHeaders , or ExcludedHeaders .

Example JSON: "HeaderMatchPattern": { "ExcludedHeaders": {"KeyToExclude1", "KeyToExclude2"} }

All -> (structure)

Inspect all headers.

IncludedHeaders -> (list)

Inspect only the headers that have a key that matches one of the strings specified here.

(string)

ExcludedHeaders -> (list)

Inspect only the headers whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the headers to match with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the headers of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request headers when they exceed 8 KB (8192 bytes) or 200 total headers. The underlying host service forwards a maximum of 200 headers and at most 8 KB of header contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the headers normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

Cookies -> (structure)

Inspect the request cookies. You must configure scope and pattern matching filters in the Cookies object, to define the set of cookies and the parts of the cookies that WAF inspects.

Only the first 8 KB (8192 bytes) of a request’s cookies and only the first 200 cookies are forwarded to WAF for inspection by the underlying host service. You must configure how to handle any oversize cookie content in the Cookies object. WAF applies the pattern matching filters to the cookies that it receives from the underlying host service.

MatchPattern -> (structure)

The filter to use to identify the subset of cookies to inspect in a web request.

You must specify exactly one setting: either All , IncludedCookies , or ExcludedCookies .

Example JSON: "CookieMatchPattern": { "IncludedCookies": {"KeyToInclude1", "KeyToInclude2", "KeyToInclude3"} }

All -> (structure)

Inspect all cookies.

IncludedCookies -> (list)

Inspect only the cookies that have a key that matches one of the strings specified here.

(string)

ExcludedCookies -> (list)

Inspect only the cookies whose keys don’t match any of the strings specified here.

(string)

MatchScope -> (string)

The parts of the cookies to inspect with the rule inspection criteria. If you specify All , WAF inspects both keys and values.

OversizeHandling -> (string)

What WAF should do if the cookies of the request are larger than WAF can inspect. WAF does not support inspecting the entire contents of request cookies when they exceed 8 KB (8192 bytes) or 200 total cookies. The underlying host service forwards a maximum of 200 cookies and at most 8 KB of cookie contents to WAF.

The options for oversize handling are the following:

  • CONTINUE - Inspect the cookies normally, according to the rule inspection criteria.

  • MATCH - Treat the web request as matching the rule statement. WAF applies the rule action to the request.

  • NO_MATCH - Treat the web request as not matching the rule statement.

TextTransformations -> (list)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. If you specify one or more transformations in a rule statement, WAF performs all transformations on the content of the request component identified by FieldToMatch , starting from the lowest priority setting, before inspecting the content for a match.

(structure)

Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection.

Priority -> (integer)

Sets the relative processing order for multiple transformations that are defined for a rule statement. WAF processes all transformations, from lowest priority to highest, before inspecting the transformed content. The priorities don’t need to be consecutive, but they must all be different.

Type -> (string)

You can specify the following transformation types:

BASE64_DECODE - Decode a Base64 -encoded string.

BASE64_DECODE_EXT - Decode a Base64 -encoded string, but use a forgiving implementation that ignores characters that aren’t valid.

CMD_LINE - Command-line transformations. These are helpful in reducing effectiveness of attackers who inject an operating system command-line command and use unusual formatting to disguise some or all of the command.

  • Delete the following characters: \ " ' ^

  • Delete spaces before the following characters: / (

  • Replace the following characters with a space: , ;

  • Replace multiple spaces with one space

  • Convert uppercase letters (A-Z) to lowercase (a-z)

COMPRESS_WHITE_SPACE - Replace these characters with a space character (decimal 32):

  • \f , formfeed, decimal 12

  • \t , tab, decimal 9

  • \n , newline, decimal 10

  • \r , carriage return, decimal 13

  • \v , vertical tab, decimal 11

  • Non-breaking space, decimal 160

COMPRESS_WHITE_SPACE also replaces multiple spaces with one space.

CSS_DECODE - Decode characters that were encoded using CSS 2.x escape rules syndata.html#characters . This function uses up to two bytes in the decoding process, so it can help to uncover ASCII characters that were encoded using CSS encoding that wouldn’t typically be encoded. It’s also useful in countering evasion, which is a combination of a backslash and non-hexadecimal characters. For example, ja\vascript for javascript.

ESCAPE_SEQ_DECODE - Decode the following ANSI C escape sequences: \a , \b , \f , \n , \r , \t , \v , \\ , \? , \' , \" , \xHH (hexadecimal), \0OOO (octal). Encodings that aren’t valid remain in the output.

HEX_DECODE - Decode a string of hexadecimal characters into a binary.

HTML_ENTITY_DECODE - Replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs these operations:

  • Replaces (ampersand)quot; with "

  • Replaces (ampersand)nbsp; with a non-breaking space, decimal 160

  • Replaces (ampersand)lt; with a “less than” symbol

  • Replaces (ampersand)gt; with >

  • Replaces characters that are represented in hexadecimal format, (ampersand)#xhhhh; , with the corresponding characters

  • Replaces characters that are represented in decimal format, (ampersand)#nnnn; , with the corresponding characters

JS_DECODE - Decode JavaScript escape sequences. If a \ u HHHH code is in the full-width ASCII code range of FF01-FF5E , then the higher byte is used to detect and adjust the lower byte. If not, only the lower byte is used and the higher byte is zeroed, causing a possible loss of information.

LOWERCASE - Convert uppercase letters (A-Z) to lowercase (a-z).

MD5 - Calculate an MD5 hash from the data in the input. The computed hash is in a raw binary form.

NONE - Specify NONE if you don’t want any text transformations.

NORMALIZE_PATH - Remove multiple slashes, directory self-references, and directory back-references that are not at the beginning of the input from an input string.

NORMALIZE_PATH_WIN - This is the same as NORMALIZE_PATH , but first converts backslash characters to forward slashes.

REMOVE_NULLS - Remove all NULL bytes from the input.

REPLACE_COMMENTS - Replace each occurrence of a C-style comment (/* ... */ ) with a single space. Multiple consecutive occurrences are not compressed. Unterminated comments are also replaced with a space (ASCII 0x20). However, a standalone termination of a comment (*/ ) is not acted upon.

REPLACE_NULLS - Replace NULL bytes in the input with space characters (ASCII 0x20 ).

SQL_HEX_DECODE - Decode SQL hex data. Example (0x414243 ) will be decoded to (ABC ).

URL_DECODE - Decode a URL-encoded value.

URL_DECODE_UNI - Like URL_DECODE , but with support for Microsoft-specific %u encoding. If the code is in the full-width ASCII code range of FF01-FF5E , the higher byte is used to detect and adjust the lower byte. Otherwise, only the lower byte is used and the higher byte is zeroed.

UTF8_TO_UNICODE - Convert all UTF-8 character sequences to Unicode. This helps input normalization, and minimizing false-positives and false-negatives for non-English languages.

ManagedRuleGroupConfigs -> (list)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

(structure)

Additional information that’s used by a managed rule group. Most managed rule groups don’t require this.

Use this for the account takeover prevention managed rule group AWSManagedRulesATPRuleSet , to provide information about the sign-in page of your application.

You can provide multiple individual ManagedRuleGroupConfig objects for any rule group configuration, for example UsernameField and PasswordField . The configuration that you provide depends on the needs of the managed rule group. For the ATP managed rule group, you provide the following individual configuration objects: LoginPath , PasswordField , PayloadType and UsernameField .

LoginPath -> (string)

The path of the login endpoint for your application. For example, for the URL https://example.com/web/login , you would provide the path /web/login .

PayloadType -> (string)

The payload type for your login endpoint, either JSON or form encoded.

UsernameField -> (structure)

Details about your login page username field.

Identifier -> (string)

The name of the username field. For example /form/username .

PasswordField -> (structure)

Details about your login page password field.

Identifier -> (string)

The name of the password field. For example /form/password .

RuleGroupReferenceStatement -> (structure)

A rule statement used to run the rules that are defined in a RuleGroup . To use this, create a rule group with your rules, then provide the ARN of the rule group in this statement.

You cannot nest a RuleGroupReferenceStatement , for example for use inside a NotStatement or OrStatement . You can only use a rule group reference statement at the top level inside a web ACL.

ARN -> (string)

The Amazon Resource Name (ARN) of the entity.

ExcludedRules -> (list)

The rules in the referenced rule group whose actions are set to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

(structure)

Specifies a single rule in a rule group whose action you want to override to Count . When you exclude a rule, WAF evaluates it exactly as it would if the rule action setting were Count . This is a useful option for testing the rules in a rule group without modifying how they handle your web traffic.

Name -> (string)

The name of the rule whose action you want to override to Count .

OverrideAction -> (structure)

The action to use in the place of the action that results from the rule group evaluation. Set the override action to none to leave the result of the rule group alone. Set it to count to override the result to count only.

You can only use this for rule statements that reference a rule group, like RuleGroupReferenceStatement and ManagedRuleGroupStatement .

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

Count -> (structure)

Override the rule group evaluation result to count only.

Note

This option is usually set to none. It does not affect how the rules in the rule group are evaluated. If you want the rules in the rule group to only count matches, do not use this and instead exclude those rules in your rule group reference statement settings.

CustomRequestHandling -> (structure)

Defines custom handling for the web request.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

InsertHeaders -> (list)

The HTTP headers to insert into the request. Duplicate header names are not allowed.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

(structure)

A custom header for custom request and response handling. This is used in CustomResponse and CustomRequestHandling .

Name -> (string)

The name of the custom header.

For custom request header insertion, when WAF inserts the header into the request, it prefixes this name x-amzn-waf- , to avoid confusion with the headers that are already in the request. For example, for the header name sample , WAF inserts the header x-amzn-waf-sample .

Value -> (string)

The value of the custom header.

None -> (structure)

Don’t override the rule group evaluation result. This is the most common setting.

VisibilityConfig -> (structure)

Defines and enables Amazon CloudWatch metrics and web request sample collection.

SampledRequestsEnabled -> (boolean)

A boolean indicating whether WAF should store a sampling of the web requests that match the rules. You can view the sampled requests through the WAF console.

CloudWatchMetricsEnabled -> (boolean)

A boolean indicating whether the associated resource sends metrics to Amazon CloudWatch. For the list of available metrics, see WAF Metrics .

MetricName -> (string)

A name of the Amazon CloudWatch metric. The name can contain only the characters: A-Z, a-z, 0-9, - (hyphen), and _ (underscore). The name can be from one to 128 characters long. It can’t contain whitespace or metric names reserved for WAF, for example “All” and “Default_Action.”

ManagedByFirewallManager -> (boolean)

Indicates whether this web ACL is managed by Firewall Manager. If true, then only Firewall Manager can delete the web ACL or any Firewall Manager rule groups in the web ACL.

LabelNamespace -> (string)

The label namespace prefix for this web ACL. All labels added by rules in this web ACL have this prefix.

  • The syntax for the label namespace prefix for a web ACL is the following: awswaf:<account ID>:webacl:<web ACL name>:

  • When a rule with a label matches a web request, WAF adds the fully qualified label to the request. A fully qualified label is made up of the label namespace from the rule group or web ACL where the rule is defined and the label from the rule, separated by a colon: <label namespace>:<label from rule>

CustomResponseBodies -> (map)

A map of custom response keys and content bodies. When you create a rule with a block action, you can send a custom response to the web request. You define these for the web ACL, and then use them in the rules and default actions that you define in the web ACL.

For information about customizing web requests and responses, see Customizing web requests and responses in WAF in the WAF Developer Guide .

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

key -> (string)

value -> (structure)

The response body to use in a custom response to a web request. This is referenced by key from CustomResponse CustomResponseBodyKey .

ContentType -> (string)

The type of content in the payload that you are defining in the Content string.

Content -> (string)

The payload of the custom response.

You can use JSON escape strings in JSON content. To do this, you must specify JSON content in the ContentType setting.

For information about the limits on count and size for custom request and response settings, see WAF quotas in the WAF Developer Guide .

CaptchaConfig -> (structure)

Specifies how WAF should handle CAPTCHA evaluations for rules that don’t have their own CaptchaConfig settings. If you don’t specify this, WAF uses its default settings for CaptchaConfig .

ImmunityTimeProperty -> (structure)

Determines how long a CAPTCHA token remains valid after the client successfully solves a CAPTCHA puzzle.

ImmunityTime -> (long)

The amount of time, in seconds, that a CAPTCHA token is valid. The default setting is 300.

LockToken -> (string)

A token used for optimistic locking. WAF returns a token to your get and list requests, to mark the state of the entity at the time of the request. To make changes to the entity associated with the token, you provide the token to operations like update and delete . WAF uses the token to ensure that no changes have been made to the entity since you last retrieved it. If a change has been made, the update fails with a WAFOptimisticLockException . If this happens, perform another get , and use the new token returned by that operation.

ApplicationIntegrationURL -> (string)

The URL to use in SDK integrations with Amazon Web Services managed rule groups. For example, you can use the integration SDKs with the account takeover prevention managed rule group AWSManagedRulesATPRuleSet . This is only populated if you are using a rule group in your web ACL that integrates with your applications in this way. For more information, see WAF client application integration in the WAF Developer Guide .