AWS::WAFRegional::ByteMatchSet - Amazon CloudFormation
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).



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

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

The AWS::WAFRegional::ByteMatchSet resource creates an Amazon WAF ByteMatchSet that identifies a part of a web request that you want to inspect.


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


{ "Type" : "AWS::WAFRegional::ByteMatchSet", "Properties" : { "ByteMatchTuples" : [ ByteMatchTuple, ... ], "Name" : String } }


Type: AWS::WAFRegional::ByteMatchSet Properties: ByteMatchTuples: - ByteMatchTuple Name: String



Specifies the bytes (typically a string that corresponds with ASCII characters) that you want Amazon WAF to search for in web requests, the location in requests that you want Amazon WAF to search, and other settings.

Required: No

Type: Array of ByteMatchTuple

Update requires: No interruption


A friendly name or description of the ByteMatchSet. You can't change Name after you create a ByteMatchSet.

Required: Yes

Type: String

Pattern: .*\S.*

Minimum: 1

Maximum: 128

Update requires: Replacement

Return values


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.



HTTP Referers

The following example defines a set of HTTP referers to match.


"BadReferers": { "Type": "AWS::WAFRegional::ByteMatchSet", "Properties": { "Name": "ByteMatch for matching bad HTTP referers", "ByteMatchTuples": [ { "FieldToMatch" : { "Type": "HEADER", "Data": "referer" }, "TargetString" : "badrefer1", "TextTransformation" : "NONE", "PositionalConstraint" : "CONTAINS" }, { "FieldToMatch" : { "Type": "HEADER", "Data": "referer" }, "TargetString" : "badrefer2", "TextTransformation" : "NONE", "PositionalConstraint" : "CONTAINS" } ] } }


BadReferers: Type: "AWS::WAFRegional::ByteMatchSet" Properties: Name: "ByteMatch for matching bad HTTP referers" ByteMatchTuples: - FieldToMatch: Type: "HEADER" Data: "referer" TargetString: "badrefer1" TextTransformation: "NONE" PositionalConstraint: "CONTAINS" - FieldToMatch: Type: "HEADER" Data: "referer" TargetString: "badrefer2" TextTransformation: "NONE" PositionalConstraint: "CONTAINS"

Associate a ByteMatchSet with a Web ACL Rule

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


"BadReferersRule" : { "Type": "AWS::WAFRegional::Rule", "Properties": { "Name": "BadReferersRule", "MetricName" : "BadReferersRule", "Predicates": [ { "DataId" : { "Ref" : "BadReferers" }, "Negated" : false, "Type" : "ByteMatch" } ] } }


BadReferersRule: Type: "AWS::WAFRegional::Rule" Properties: Name: "BadReferersRule" MetricName: "BadReferersRule" Predicates: - DataId: Ref: "BadReferers" Negated: false Type: "ByteMatch"

Create a Web ACL

The following example associates the BadReferersRule rule with a web ACL. The web ACL allows all requests except for ones with referers that match the BadReferersRule rule.


"MyWebACL": { "Type": "AWS::WAFRegional::WebACL", "Properties": { "Name": "WebACL to block blacklisted IP addresses", "DefaultAction": { "Type": "ALLOW" }, "MetricName" : "MyWebACL", "Rules": [ { "Action" : { "Type" : "BLOCK" }, "Priority" : 1, "RuleId" : { "Ref" : "BadReferersRule" } } ] } }


MyWebACL: Type: "AWS::WAFRegional::WebACL" Properties: Name: "WebACL to block blacklisted IP addresses" DefaultAction: Type: "ALLOW" MetricName: "MyWebACL" Rules: - Action: Type: "BLOCK" Priority: 1 RuleId: Ref: "BadReferersRule"