[ aws . sts ]



Decodes additional information about the authorization status of a request from an encoded message returned in response to an Amazon Web Services request.

For example, if a user is not authorized to perform an operation that he or she has requested, the request returns a Client.UnauthorizedOperation response (an HTTP 403 response). Some Amazon Web Services operations additionally return an encoded message that can provide details about this authorization failure.


Only certain Amazon Web Services operations return an encoded authorization message. The documentation for an individual operation indicates whether that operation returns an encoded message in addition to returning an HTTP code.

The message is encoded because the details of the authorization status can contain privileged information that the user who requested the operation should not see. To decode an authorization status message, a user must be granted permissions through an IAM policy to request the DecodeAuthorizationMessage (sts:DecodeAuthorizationMessage ) action.

The decoded message includes the following type of information:

  • Whether the request was denied due to an explicit deny or due to the absence of an explicit allow. For more information, see Determining Whether a Request is Allowed or Denied in the IAM User Guide .
  • The principal who made the request.
  • The requested action.
  • The requested resource.
  • The values of condition keys in the context of the user’s request.

See also: AWS API Documentation


--encoded-message <value>
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]
[--endpoint-url <value>]
[--output <value>]
[--query <value>]
[--profile <value>]
[--region <value>]
[--version <value>]
[--color <value>]
[--ca-bundle <value>]
[--cli-read-timeout <value>]
[--cli-connect-timeout <value>]
[--cli-binary-format <value>]


--encoded-message (string)

The encoded message that was returned with the response.

--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. The generated JSON skeleton is not stable between versions of the AWS CLI and there are no backwards compatibility guarantees in the JSON skeleton generated.

Global Options

--debug (boolean)

Turn on debug logging.

--endpoint-url (string)

Override command’s default URL with the given URL.

--no-verify-ssl (boolean)

By default, the AWS CLI uses SSL when communicating with AWS services. For each SSL connection, the AWS CLI will verify SSL certificates. This option overrides the default behavior of verifying SSL certificates.

--no-paginate (boolean)

Disable automatic pagination.

--output (string)

The formatting style for command output.

  • json
  • text
  • table
  • yaml
  • yaml-stream

--query (string)

A JMESPath query to use in filtering the response data.

--profile (string)

Use a specific profile from your credential file.

--region (string)

The region to use. Overrides config/env settings.

--version (string)

Display the version of this tool.

--color (string)

Turn on/off color output.

  • on
  • off
  • auto

--no-sign-request (boolean)

Do not sign requests. Credentials will not be loaded if this argument is provided.

--ca-bundle (string)

The CA certificate bundle to use when verifying SSL certificates. Overrides config/env settings.

--cli-read-timeout (int)

The maximum socket read time in seconds. If the value is set to 0, the socket read will be blocking and not timeout. The default value is 60 seconds.

--cli-connect-timeout (int)

The maximum socket connect time in seconds. If the value is set to 0, the socket connect will be blocking and not timeout. The default value is 60 seconds.

--cli-binary-format (string)

The formatting style to be used for binary blobs. The default format is base64. The base64 format expects binary blobs to be provided as a base64 encoded string. The raw-in-base64-out format preserves compatibility with AWS CLI V1 behavior and binary values must be passed literally. When providing contents from a file that map to a binary blob fileb:// will always be treated as binary and use the file contents directly regardless of the cli-binary-format setting. When using file:// the file contents will need to properly formatted for the configured cli-binary-format.

  • base64
  • raw-in-base64-out

--no-cli-pager (boolean)

Disable cli pager for output.

--cli-auto-prompt (boolean)

Automatically prompt for CLI input parameters.

--no-cli-auto-prompt (boolean)

Disable automatically prompt for CLI input parameters.



To use the following examples, you must have the AWS CLI installed and configured. See the Getting started guide in the AWS CLI User Guide for more information.

Unless otherwise stated, all examples have unix-like quotation rules. These examples will need to be adapted to your terminal’s quoting rules. See Using quotation marks with strings in the AWS CLI User Guide .

To decode an encoded authorization message returned in response to a request

The following decode-authorization-message example decodes additional information about the authorization status of a request from an encoded message returned in response to an Amazon Web Services request.

aws sts decode-authorization-message \
    --encoded-message EXAMPLEWodyRNrtlQARDip-eTA6i6DrlUhHhPQrLWB_lAbl5pAKxl9mPDLexYcGBreyIKQC1BGBIpBKr3dFDkwqeO7e2NMk5j_hmzAiChJN-8oy3EwiCjkUW5fdRNjcRvscGlUo_MhqHqHpR-Ojau7BMjOTWwOtHPhV_Zaz87yENdipr745EjQwRd5LaoL3vN8_5ZfA9UiBMKDgVh1gjqZJFUiQoubv78V1RbHNYnK44ElGKmUWYa020I1y6TNS9LXoNmc62GzkfGvoPGhD13br5tXEOo1rAm3vsPewRDFNkYL-4_1MWWezhRNEpqvXBDXLI9xEux7YYkRtjd45NJLFzZynBUubV8NHOevVuighd1Mvz3OiA-1_oPSe4TBtjfN9s7kjU1z70WpVbUgrLVp1xXTK1rf9Ea7t8shPd-3VzKhjS5tLrweFxNOKwV2GtT76B_fRp8HTYz-pOu3FZjwYStfvTb3GHs3-6rLribGO9jZOktkfE6vqxlFzLyeDr4P2ihC1wty9tArCvvGzIAUNmARQJ2VVWPxioqgoqCzMaDMZEO7wkku7QeakEVZdf00qlNLMmcaVZb1UPNqD-JWP5pwe_mAyqh0NLw-r1S56YC_90onj9A80sNrHlI-tIiNd7tgNTYzDuPQYD2FMDBnp82V9eVmYGtPp5NIeSpuf3fOHanFuBZgENxZQZ2dlH3xJGMTtYayzZrRXjiq_SfX9zeBbpCvrD-0AJK477RM84vmtCrsUpJgx-FaoPIb8LmmKVBLpIB0iFhU9sEHPqKHVPi6jdxXqKaZaFGvYVmVOiuQdNQKuyk0p067POFrZECLjjOtNPBOZCcuEKEXAMPLE


    "DecodedMessage": "{\"allowed\":false,\"explicitDeny\":true,\"matchedStatements\":{\"items\":[{\"statementId\":\"VisualEditor0\",\"effect\":\"DENY\",\"principals\":{\"items\":[{\"value\":\"AROA123456789EXAMPLE\"}]},\"principalGroups\":{\"items\":[]},\"actions\":{\"items\":[{\"value\":\"ec2:RunInstances\"}]},\"resources\":{\"items\":[{\"value\":\"*\"}]},\"conditions\":{\"items\":[]}}]},\"failures\":{\"items\":[]},\"context\":{\"principal\":{\"id\":\"AROA123456789EXAMPLE:Ana\",\"arn\":\"arn:aws:sts::111122223333:assumed-role/Developer/Ana\"},\"action\":\"RunInstances\",\"resource\":\"arn:aws:ec2:us-east-1:111122223333:instance/*\",\"conditions\":{\"items\":[{\"key\":\"ec2:MetadataHttpPutResponseHopLimit\",\"values\":{\"items\":[{\"value\":\"2\"}]}},{\"key\":\"ec2:InstanceMarketType\",\"values\":{\"items\":[{\"value\":\"on-demand\"}]}},{\"key\":\"aws:Resource\",\"values\":{\"items\":[{\"value\":\"instance/*\"}]}},{\"key\":\"aws:Account\",\"values\":{\"items\":[{\"value\":\"111122223333\"}]}},{\"key\":\"ec2:AvailabilityZone\",\"values\":{\"items\":[{\"value\":\"us-east-1f\"}]}},{\"key\":\"ec2:ebsOptimized\",\"values\":{\"items\":[{\"value\":\"false\"}]}},{\"key\":\"ec2:IsLaunchTemplateResource\",\"values\":{\"items\":[{\"value\":\"false\"}]}},{\"key\":\"ec2:InstanceType\",\"values\":{\"items\":[{\"value\":\"t2.micro\"}]}},{\"key\":\"ec2:RootDeviceType\",\"values\":{\"items\":[{\"value\":\"ebs\"}]}},{\"key\":\"aws:Region\",\"values\":{\"items\":[{\"value\":\"us-east-1\"}]}},{\"key\":\"ec2:MetadataHttpEndpoint\",\"values\":{\"items\":[{\"value\":\"enabled\"}]}},{\"key\":\"aws:Service\",\"values\":{\"items\":[{\"value\":\"ec2\"}]}},{\"key\":\"ec2:InstanceID\",\"values\":{\"items\":[{\"value\":\"*\"}]}},{\"key\":\"ec2:MetadataHttpTokens\",\"values\":{\"items\":[{\"value\":\"required\"}]}},{\"key\":\"aws:Type\",\"values\":{\"items\":[{\"value\":\"instance\"}]}},{\"key\":\"ec2:Tenancy\",\"values\":{\"items\":[{\"value\":\"default\"}]}},{\"key\":\"ec2:Region\",\"values\":{\"items\":[{\"value\":\"us-east-1\"}]}},{\"key\":\"aws:ARN\",\"values\":{\"items\":[{\"value\":\"arn:aws:ec2:us-east-1:111122223333:instance/*\"}]}}]}}}"

For more information, see Policy evaluation logic in the AWS IAM User Guide.


DecodedMessage -> (string)

The API returns a response with the decoded message.