Control: 3.4 Ensure S3 bucket access logging is enabled on the CloudTrail S3 bucket

Description

S3 Bucket Access Logging generates a log that contains access records for each request made to your S3 bucket. An access log record contains details about the request, such as the request type, the resources specified in the request worked, and the time and date the request was processed. It is recommended that bucket access logging be enabled on the CloudTrail S3 bucket.

By enabling S3 bucket logging on target S3 buckets, it is possible to capture all events which may affect objects within any target buckets. Configuring logs to be placed in a separate bucket allows access to log information which can be useful in security and incident response workflows.

Remediation

Perform the following to enable S3 bucket logging:

From Console:

1. Sign in to the AWS Management Console and open the S3 console at https://console.aws.amazon.com/s3.
2. Under All Buckets click on the target S3 bucket
3. Click on Properties in the top right of the console
4. Under Bucket: <s3_bucket_for_cloudtrail> click on Logging
5. Configure bucket logging

• Click on the Enabled checkbox
• Select Target Bucket from list
• Enter a Target Prefix

6. Click Save.

From Command Line:

1. Get the name of the S3 bucket that CloudTrail is logging to:

aws cloudtrail describe-trails --region <region-name> --query trailList[*].S3BucketName

2. Copy and add target bucket name at <Logging_BucketName>, Prefix for logfile at <LogFilePrefix> and optionally add an email address in the following template and save it as <FileName.Json>:

{
"LoggingEnabled":{
"TargetBucket": "<Logging_BucketName>",
"TargetPrefix": "<LogFilePrefix>",
"TargetGrants": [
{
"Grantee":{
"Type": "AmazonCustomerByEmail",
"EmailAddress": "<EmailID>"
},
"Permission": "FULL_CONTROL"
}
]
}
}

3. Run the put-bucket-logging command with bucket name and <FileName.Json> as input: for more information refer to put-bucket-logging:

aws s3api put-bucket-logging --bucket <BucketName> --bucket-logging-status file://<FileName.Json>

Default Value:

Logging is disabled.