AWS S3 public WRITE permission Critical

AWS S3 bucket allows public WRITE permission. Make sure AWS S3 bucket prohibits WRITE permission to everyone.

Detector ID
cloudformation/public-write-s3-bucket-cloudformation@v1.0
Category
Common Weakness Enumeration (CWE) external icon

Noncompliant example

1Resources:
2  Resource:
3    Type: AWS::S3::Bucket
4    Properties:
5      BucketName: !Ref BucketName
6      NotificationConfiguration:
7        LambdaConfigurations:
8          - Event: 's3:ObjectCreated:*'
9            Function: !GetAtt InvokedFunction.Arn
10      # Noncompliant: S3 bucket allows WRITE permissions to everyone.
11      AccessControl: PublicReadWrite
12      LoggingConfiguration:
13        DestinationBucketName: String
14        LogFilePrefix: String
15      PublicAccessBlockConfiguration:
16        BlockPublicAcls: true
17        BlockPublicPolicy: true
18        IgnorePublicAcls: true
19        RestrictPublicBuckets: true
20      VersioningConfiguration:
21        Status: Enabled

Compliant example

1Resources:
2  Resource:
3    Type: AWS::S3::Bucket
4    Properties:
5      BucketName: !Ref BucketName
6      NotificationConfiguration:
7        LambdaConfigurations:
8          - Event: 's3:ObjectCreated:*'
9            Function: !GetAtt InvokedFunction.Arn
10      # Compliant: S3 bucket does not allow WRITE permissions to everyone.
11      AccessControl: Private
12      LoggingConfiguration:
13        DestinationBucketName: String
14        LogFilePrefix: String
15      PublicAccessBlockConfiguration:
16        BlockPublicAcls: true
17        BlockPublicPolicy: true
18        IgnorePublicAcls: true
19        RestrictPublicBuckets: true
20      VersioningConfiguration:
21        Status: Enabled