WAF / Client / update_xss_match_set

update_xss_match_set#

WAF.Client.update_xss_match_set(**kwargs)#

Note

This is AWS WAF Classic documentation. For more information, see AWS WAF Classic in the developer guide.

For the latest version of AWS WAF, use the AWS WAFV2 API and see the AWS WAF Developer Guide. With the latest version, AWS WAF has a single set of endpoints for regional and global use.

Inserts or deletes XssMatchTuple objects (filters) in an XssMatchSet. For each XssMatchTuple object, you specify the following values:

  • Action: Whether to insert the object into or delete the object from the array. To change an XssMatchTuple, you delete the existing object and add a new one.

  • FieldToMatch: The part of web requests that you want AWS WAF to inspect and, if you want AWS WAF to inspect a header or custom query parameter, the name of the header or parameter.

  • TextTransformation: Which text transformation, if any, to perform on the web request before inspecting the request for cross-site scripting attacks. You can only specify a single type of TextTransformation.

You use XssMatchSet objects to specify which CloudFront requests that you want to allow, block, or count. For example, if you’re receiving requests that contain cross-site scripting attacks in the request body and you want to block the requests, you can create an XssMatchSet with the applicable settings, and then configure AWS WAF to block the requests.

To create and configure an XssMatchSet, perform the following steps:

  • Submit a CreateXssMatchSet request.

  • Use GetChangeToken to get the change token that you provide in the ChangeToken parameter of an UpdateIPSet request.

  • Submit an UpdateXssMatchSet request to specify the parts of web requests that you want AWS WAF to inspect for cross-site scripting attacks.

For more information about how to use the AWS WAF API to allow or block HTTP requests, see the AWS WAF Developer Guide.

See also: AWS API Documentation

Request Syntax

response = client.update_xss_match_set(
    XssMatchSetId='string',
    ChangeToken='string',
    Updates=[
        {
            'Action': 'INSERT'|'DELETE',
            'XssMatchTuple': {
                'FieldToMatch': {
                    'Type': 'URI'|'QUERY_STRING'|'HEADER'|'METHOD'|'BODY'|'SINGLE_QUERY_ARG'|'ALL_QUERY_ARGS',
                    'Data': 'string'
                },
                'TextTransformation': 'NONE'|'COMPRESS_WHITE_SPACE'|'HTML_ENTITY_DECODE'|'LOWERCASE'|'CMD_LINE'|'URL_DECODE'
            }
        },
    ]
)
Parameters:

  • XssMatchSetId (string) –

    [REQUIRED]

    The XssMatchSetId of the XssMatchSet that you want to update. XssMatchSetId is returned by CreateXssMatchSet and by ListXssMatchSets.

  • ChangeToken (string) –

    [REQUIRED]

    The value returned by the most recent call to GetChangeToken.

  • Updates (list) –

    [REQUIRED]

    An array of XssMatchSetUpdate objects that you want to insert into or delete from an XssMatchSet. For more information, see the applicable data types:

    • XssMatchSetUpdate: Contains Action and XssMatchTuple

    • XssMatchTuple: Contains FieldToMatch and TextTransformation

    • FieldToMatch: Contains Data and Type

    • (dict) –

      Note

      This is AWS WAF Classic documentation. For more information, see AWS WAF Classic in the developer guide.

      For the latest version of AWS WAF, use the AWS WAFV2 API and see the AWS WAF Developer Guide. With the latest version, AWS WAF has a single set of endpoints for regional and global use.

      Specifies the part of a web request that you want to inspect for cross-site scripting attacks and indicates whether you want to add the specification to an XssMatchSet or delete it from an XssMatchSet.

      • Action (string) – [REQUIRED]

        Specify INSERT to add an XssMatchSetUpdate to an XssMatchSet. Use DELETE to remove an XssMatchSetUpdate from an XssMatchSet.

      • XssMatchTuple (dict) – [REQUIRED]

        Specifies the part of a web request that you want AWS WAF to inspect for cross-site scripting attacks and, if you want AWS WAF to inspect a header, the name of the header.

        • FieldToMatch (dict) – [REQUIRED]

          Specifies where in a web request to look for cross-site scripting attacks.

          • Type (string) – [REQUIRED]

            The part of the web request that you want AWS WAF to search for a specified string. Parts of a request that you can search include the following:

            • HEADER: A specified request header, for example, the value of the User-Agent or Referer header. If you choose HEADER for the type, specify the name of the header in Data.

            • METHOD: The HTTP method, which indicated the type of operation that the request is asking the origin to perform. Amazon CloudFront supports the following methods: DELETE, GET, HEAD, OPTIONS, PATCH, POST, and PUT.

            • QUERY_STRING: A query string, which is the part of a URL that appears after a ? character, if any.

            • URI: The part of a web request that identifies a resource, for example, /images/daily-ad.jpg.

            • BODY: 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. The request body immediately follows the request headers. Note that only the first 8192 bytes of the request body are forwarded to AWS WAF for inspection. To allow or block requests based on the length of the body, you can create a size constraint set. For more information, see CreateSizeConstraintSet.

            • SINGLE_QUERY_ARG: The parameter in the query string that you will inspect, such as UserName or SalesRegion. The maximum length for SINGLE_QUERY_ARG is 30 characters.

            • ALL_QUERY_ARGS: Similar to SINGLE_QUERY_ARG, but rather than inspecting a single parameter, AWS WAF will inspect all parameters within the query for the value or regex pattern that you specify in TargetString.

          • Data (string) –

            When the value of Type is HEADER, enter the name of the header that you want AWS WAF to search, for example, User-Agent or Referer. The name of the header is not case sensitive.

            When the value of Type is SINGLE_QUERY_ARG, enter the name of the parameter that you want AWS WAF to search, for example, UserName or SalesRegion. The parameter name is not case sensitive.

            If the value of Type is any other value, omit Data.

        • TextTransformation (string) – [REQUIRED]

          Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass AWS WAF. If you specify a transformation, AWS WAF performs the transformation on FieldToMatch before inspecting it for a match.

          You can only specify a single type of TextTransformation.

          CMD_LINE

          When you’re concerned that attackers are injecting an operating system command line command and using unusual formatting to disguise some or all of the command, use this option to perform the following transformations:

          • 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

          Use this option to replace the following 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.

          HTML_ENTITY_DECODE

          Use this option to replace HTML-encoded characters with unencoded characters. HTML_ENTITY_DECODE performs the following 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

          LOWERCASE

          Use this option to convert uppercase letters (A-Z) to lowercase (a-z).

          URL_DECODE

          Use this option to decode a URL-encoded value.

          NONE

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

Return type:

dict

Returns:

Response Syntax

{
    'ChangeToken': 'string'
}

Response Structure

  • (dict) –

    The response to an UpdateXssMatchSets request.

    • ChangeToken (string) –

      The ChangeToken that you used to submit the UpdateXssMatchSet request. You can also use this value to query the status of the request. For more information, see GetChangeTokenStatus.

Exceptions

Examples

The following example deletes an XssMatchTuple object (filters) in an XssMatchSet with the ID example1ds3t-46da-4fdb-b8d5-abc321j569j5.

response = client.update_xss_match_set(
    ChangeToken='abcd12f2-46da-4fdb-b8d5-fbd4c466928f',
    Updates=[
        {
            'Action': 'DELETE',
            'XssMatchTuple': {
                'FieldToMatch': {
                    'Type': 'QUERY_STRING',
                },
                'TextTransformation': 'URL_DECODE',
            },
        },
    ],
    XssMatchSetId='example1ds3t-46da-4fdb-b8d5-abc321j569j5',
)

print(response)

Expected Output:

{
    'ChangeToken': 'abcd12f2-46da-4fdb-b8d5-fbd4c466928f',
    'ResponseMetadata': {
        '...': '...',
    },
}