Using service-linked roles for AWS WAF

AWS WAF uses AWS Identity and Access Management (IAM) service-linked roles. A service-linked role is a unique type of IAM role that is linked directly to AWS WAF. Service-linked roles are predefined by AWS WAF and include all the permissions that the service requires to call other AWS services on your behalf.

A service-linked role makes setting up AWS WAF easier because you don’t have to manually add the necessary permissions. AWS WAF defines the permissions of its service-linked roles, and unless defined otherwise, only AWS WAF can assume its roles. The defined permissions include the trust policy and the permissions policy. That permissions policy can't be attached to any other IAM entity.

You can delete a service-linked role only after first deleting the role's related resources. This protects your AWS WAF resources because you can't inadvertently remove permission to access the resources.

For information about other services that support service-linked roles, see AWS Services That Work with IAM and look for the services that have Yes in the Service-Linked Role column. Choose a Yes with a link to view the service-linked role documentation for that service.

Service-linked role permissions for AWS WAF

AWS WAF uses the service-linked role AWSServiceRoleForWAFV2Logging.

AWS WAF uses this service-linked role to write logs to Amazon Data Firehose. This role is used only if you enable logging in AWS WAF. For more information, see Logging AWS WAF web ACL traffic.

The AWSServiceRoleForWAFV2Logging service-linked role trusts the service to assume the role wafv2.amazonaws.com.

The permissions policies of the role allows AWS WAF to complete the following actions on the specified resources:

• Action: firehose:PutRecord and firehose:PutRecordBatch on Amazon Data Firehose data stream resources with a name that starts with "aws-waf-logs-." For example, aws-waf-logs-us-east-2-analytics.

You must configure permissions to allow an IAM entity (such as a user, group, or role) to create, edit, or delete a service-linked role. For more information, see Service-Linked Role Permissions in the IAM User Guide.

Creating a service-linked role for AWS WAF

You don't need to manually create a service-linked role. When you enable AWS WAF logging on the AWS Management Console, or you make a PutLoggingConfiguration request in the AWS WAF CLI or the AWS WAF API, AWS WAF creates the service-linked role for you.

You must have the iam:CreateServiceLinkedRole permission to enable logging.

If you delete this service-linked role, and then need to create it again, you can use the same process to recreate the role in your account. When you enable AWS WAF logging, AWS WAF creates the service-linked role for you again.

Editing a service-linked role for AWS WAF

AWS WAF doesn't allow you to edit the AWSServiceRoleForWAFV2Logging service-linked role. After you create a service-linked role, you can't change the name of the role because various entities might reference the role. However, you can edit the description of the role using IAM. For more information, see Editing a Service-Linked Role in the IAM User Guide.

Deleting a service-linked role for AWS WAF

If you no longer need to use a feature or service that requires a service-linked role, we recommend that you delete that role. That way you don’t have an unused entity that is not actively monitored or maintained. However, you must clean up the resources for your service-linked role before you can manually delete it.

Note

If the AWS WAF service is using the role when you try to delete the resources, then the deletion might fail. If that happens, wait for a few minutes and try the operation again.

To delete AWS WAF resources used by the AWSServiceRoleForWAFV2Logging

1. On the AWS WAF console, remove logging from every web ACL. For more information, see Logging AWS WAF web ACL traffic.

2. Using the API or CLI, submit a DeleteLoggingConfiguration request for each web ACL that has logging enabled. For more information, see AWS WAF API Reference.

To manually delete the service-linked role using IAM

Use the IAM console, the IAM CLI, or the IAM API to delete the AWSServiceRoleForWAFV2Logging service-linked role. For more information, see Deleting a Service-Linked Role in the IAM User Guide.

Supported Regions for AWS WAF service-linked roles

AWS WAF supports using service-linked roles in all of the regions where the service is available. For more information, see AWS WAF endpoints and quotas.