Managing of individual rules in an ACL deployed by AWS Firewall Manager

Hello,

Unfortunately, there is no public document which specifies the use case for individual account administrators to add rules/rule groups inside the WebACL managed by Firewall Manager using CDK.

• When you create the Firewall Manager service policy for WAFv2 type, it will create the WebACL resource and adds PreProcessFirewallManagerRuleGroups and PostProcessFirewallManagerRuleGroups properties. Document [1] explains these two properties can only be defined by Firewall Manager.

• These properties cannot be added directly to the AWS::WAFV2::WebACL resource if you are using CloudFormation template for example. The API reference guide [2] defines the properties with AWS CDK CloudFormation Resources.

• If your use case involves CloudFormation to manage the rules on Firewall Managed WebACLs, then you can use Lambda backed custom resource. In the custom resource Lambda function, you can use UpdateWebACL API calls to create or modify the rules on the WebACL resources. [3]

We recommend to use AWS Console or CLI to avoid any validation issues with CDK in this particular case.