AWS Config
Developer Guide

internet-gateway-authorized-vpc-only

Checks that Internet gateways (IGWs) are only attached to an authorized Amazon Virtual Private Cloud (VPCs). The rule is NON_COMPLIANT if IGWs are not attached to an authorized VPC.

Identifier: INTERNET_GATEWAY_AUTHORIZED_VPC_ONLY

Trigger type: Configuration changes

AWS Region: All supported AWS regions

Parameters:

authorizedVpcIds

Comma-separated list of the authorized VPC IDs with attached IGWs. If parameter is not provided all attached IGWs will be NON_COMPLIANT.

AWS CloudFormation template

To create AWS Config managed rules with AWS CloudFormation templates, see Creating AWS Config Managed Rules With AWS CloudFormation Templates.