AWS Identity and Access Management (IAM) Access Analyzer now enables you to validate access before deploying permissions changes. IAM Access Analyzer uses comprehensive policy analysis to provide provable security and generate findings for resource access. Now with IAM Access Analyzer, you can prevent public and cross-account access before you set permissions. You can preview findings and validate that your policy changes grant only intended access to your resources. By previewing findings, you can prevent unintended access before you deploy permissions.
Source:: Amazon AWS