Amazon Web Services recently introduced a new feature that lets administrators block public access to their data on S3.

The feature, called “Amazon S3 Block Public Access,” is really a group of four security settings that administrators can turn on or off across their entire AWS account or on a per-bucket basis. Once the settings are turned on, they apply to the user’s current environment, as well as to any buckets they create in the future.

The settings — which can be accessed via the S3 console, the command-line interface or the S3 API — are as follows:

• Block new public ACLs and uploading public objects
• Remove public access granted through public ACLs
• Block new public bucket policies
• Block public and cross-account access to buckets that have public policies

Reference: https://docs.aws.amazon.com/AmazonS3/latest/dev/access-control-block-public-access.html