AWS Best Practices: Real-World Data

[jhwong]

We've continued our blog series on AWS Best Practices, and just published: https://www.netskope.com/blog/a-real-world-look-at-aws-best-practices-logging . Although CloudTrail is a well-trodden subject for AWS Security, there were still a few interesting findings among a slice of our customer base:

1. Enable VPC flow logs: 81% of VPCs do not have VPC flow logging enabled, which will hinder incident response and investigations.

2. Encrypt CloudTrail logs at rest: 91% of CloudTrail logs are not encrypted at rest. Encryption at rest supports data compliance controls and is easy to do.

3. Ensure S3 bucket access logging is enabled for CloudTrail buckets: 41% of CloudTrail buckets do not have server access logging enabled. Logging should be enabled for all CloudTrail S3 buckets.

4. Ensure CloudTrail logs are integrated with CloudWatch or a SIEM: 54% of CloudTrails are not integrated with CloudWatch. These should be reviewed to ensure they are integrated with a production log search service or SIEM.

If your AWS accounts fall into these categories, we'd like to understand more about whether costs, security risk of assets, alternative controls/products, or other factors play into these controls from the CIS benchmark?

As an example, although encryption at rest using AWS managed keys may not buy a lot from a security-viewpoint, it does from a compliance viewpoint. If the cost is free to negligible, what prevents an organization from encrypting CloudTrail logs at rest on the respective S3 bucket?