More Info:

S3 buckets should not allow WRITE access to AWS authenticated users through S3 ACLs.

Risk Level

Medium

Address

Security

Compliance Standards

CBP, HIPAA

Triage and Remediation

Remediation

Sure, here are the step by step instructions to remediate the S3 Bucket Should Not Allow WRITE Access to Authenticated Users misconfiguration for AWS using AWS console:

  1. Log in to your AWS Management Console.
  2. Go to the S3 service.
  3. Select the bucket that is misconfigured.
  4. Click on the “Permissions” tab.
  5. Click on “Bucket Policy”.
  6. Remove any policies that allow write access to authenticated users.
  7. You can also add a policy that explicitly denies write access to authenticated users.

Here is an example of a policy that denies write access to authenticated users:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "DenyAuthenticatedUsers",
            "Effect": "Deny",
            "Principal": {
                "AWS": "*"
            },
            "Action": [
                "s3:PutObject",
                "s3:DeleteObject",
                "s3:PutObjectAcl",
                "s3:PutObjectVersionAcl"
            ],
            "Resource": [
                "arn:aws:s3:::bucket-name/*"
            ],
            "Condition": {
                "StringEquals": {
                    "aws:PrincipalType": "AuthenticatedUser"
                }
            }
        }
    ]
}
  1. Click on “Save” to apply the changes.

That’s it! You have now successfully remediated the S3 Bucket Should Not Allow WRITE Access to Authenticated Users misconfiguration for AWS using AWS console.

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