AWS CloudFormation
User Guide (Version )

AWS::WAF::XssMatchSet

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.

A complex type that contains XssMatchTuple objects, which specify the parts of web requests 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. If a XssMatchSet contains more than one XssMatchTuple object, a request needs to include cross-site scripting attacks in only one of the specified parts of the request to be considered a match.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Type" : "AWS::WAF::XssMatchSet", "Properties" : { "Name" : String, "XssMatchTuples" : [ XssMatchTuple, ... ] } }

YAML

Type: AWS::WAF::XssMatchSet Properties: Name: String XssMatchTuples: - XssMatchTuple

Properties

Name

The name, if any, of the XssMatchSet.

Required: Yes

Type: String

Minimum: 1

Maximum: 128

Update requires: Replacement

XssMatchTuples

Specifies the parts of web requests that you want to inspect for cross-site scripting attacks.

Required: Yes

Type: List of XssMatchTuple

Update requires: No interruption

Return Values

Ref

When you pass the logical ID of this resource to the intrinsic Ref function, Ref returns the resource physical ID, such as 1234a1a-a1b1-12a1-abcd-a123b123456.

For more information about using the Ref function, see Ref.

Examples

Define Which Part of a Request to Check for Cross-site Scripting

The following example looks for cross-site scripting in the URI or query string of an HTTP request.

JSON

"DetectXSS": { "Type": "AWS::WAF::XssMatchSet", "Properties": { "Name": "XssMatchSet", "XssMatchTuples": [ { "FieldToMatch": { "Type": "URI" }, "TextTransformation": "NONE" }, { "FieldToMatch": { "Type": "QUERY_STRING" }, "TextTransformation": "NONE" } ] } }

YAML

DetectXSS: Type: "AWS::WAF::XssMatchSet" Properties: Name: "XssMatchSet" XssMatchTuples: - FieldToMatch: Type: "URI" TextTransformation: "NONE" - FieldToMatch: Type: "QUERY_STRING" TextTransformation: "NONE"

Associate an XssMatchSet with a Web ACL Rule

The following example associates the DetectXSS match set with a web access control list (ACL) rule.

JSON

"XSSRule" : { "Type": "AWS::WAF::Rule", "Properties": { "Name": "XSSRule", "MetricName" : "XSSRule", "Predicates": [ { "DataId" : { "Ref" : "DetectXSS" }, "Negated" : false, "Type" : "XssMatch" } ] } }

YAML

XSSRule: Type: "AWS::WAF::Rule" Properties: Name: "XSSRule" MetricName: "XSSRule" Predicates: - DataId: Ref: "DetectXSS" Negated: false Type: "XssMatch"

Create a Web ACL

The following example associates the XSSRule rule with a web ACL. The web ACL allows all requests except for ones that contain cross-site scripting in the URI or query string of an HTTP request.

JSON

"MyWebACL": { "Type": "AWS::WAF::WebACL", "Properties": { "Name": "Web ACL to block cross-site scripting", "DefaultAction": { "Type": "ALLOW" }, "MetricName" : "DetectXSSWebACL", "Rules": [ { "Action" : { "Type" : "BLOCK" }, "Priority" : 1, "RuleId" : { "Ref" : "XSSRule" } } ] } }

YAML

MyWebACL: Type: "AWS::WAF::WebACL" Properties: Name: "Web ACL to block cross-site scripting" DefaultAction: Type: "ALLOW" MetricName: "DetectXSSWebACL" Rules: - Action: Type: "BLOCK" Priority: 1 RuleId: Ref: "XSSRule"