Posted On: Dec 2, 2019

Access Analyzer for S3 is a new feature that monitors your access policies, ensuring that the policies provide only the intended access to your S3 resources. Access Analyzer for S3 evaluates your bucket access policies and enables you to discover and swiftly remediate buckets with potentially unintended access.

Access Analyzer for S3 alerts you when you have a bucket that is configured to allow access to anyone on the internet or that is shared with other AWS accounts. You receive insights or ‘findings’ into the source and level of public or shared access. For example, Access Analyzer for S3 will proactively inform you if read or write access were unintendedly provided through an access control list (ACL) or bucket policy. With these insights, you can immediately set or restore the intended access policy.

When reviewing results that show potentially shared access to a bucket, you can Block All Public Access to the bucket with a single click in the S3 Management console. You can also drill down into bucket level permission settings to configure granular levels of access. For specific and verified use cases that require public access, such as static website hosting, you can acknowledge and archive the findings on a bucket to record that you intend for the bucket to remain public or shared. You can revisit and modify these bucket configurations at any time. For auditing purposes, Access Analyzer for S3 findings can be downloaded as a CSV report.

To get started with Access Analyzer for S3, visit the IAM console to enable the AWS Identity and Access Management (IAM) Access Analyzer. When you do this, Access Analyzer for S3 will automatically be visible in the S3 Management Console.

Access Analyzer for S3 is available at no additional cost in the S3 Management Console in all commercial AWS Regions, excluding the AWS China (Beijing) Region and the AWS China (Ningxia) Region. Access Analyzer for S3 is also available through APIs in the AWS GovCloud (US) Regions.

To learn more, please read the blog post.