More Info:

AWS S3 buckets should not allow public WRITE_ACP access. Granting public “WRITE_ACP” access to your AWS S3 buckets can allow anonymous users to edit their ACL permissions and eventually be able to view, upload, modify and delete S3 objects within the bucket without restrictions.

Risk Level

High

Address

Security

Compliance Standards

NIST, PCIDSS

Triage and Remediation

Remediation

To remediate the misconfiguration “S3 Bucket Should Not Allow Public WRITE_ACP Access” for AWS using the AWS console, please follow the below steps:

  1. Log in to your AWS console.
  2. Navigate to S3 service.
  3. Select the bucket that has public WRITE_ACP access.
  4. Click on the “Permissions” tab.
  5. Scroll down to “Access Control List (ACL)” and click on it.
  6. Look for any entries that have the “Grantee” set to “All Users” or “Authenticated Users”.
  7. If you find any such entries, select them and click on the “Revoke” button to remove the public WRITE_ACP access.
  8. Click on the “Save” button to save the changes.

Once you have completed the above steps, your S3 bucket will no longer have public WRITE_ACP access and will be remediated.

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