Best Practices for Securing Data in Amazon S3 Buckets (2023 Guide)
a. Bucket Policies and ACLs: Use AWS Identity and Access Management (IAM) with S3 bucket policies to build granular access controls. Only allow access to the essential users and resources.
b. Enable Encryption: Use server-side encryption to protect data stored in S3 buckets. AWS offers several choices, including SSE-S3, SSE-KMS, and SSE-C. This ensures that data is encrypted at rest.
c. Versioning: Enable versioning in S3 buckets to keep track of object changes. This aids in recovering from unintentional deletions or malicious adjustments.
d. Logging and Monitoring: Turn on AWS CloudTrail logging to track all API calls to the S3 bucket. Enable S3 server access logging to track access requests to the bucket.
e. Access Logging and Audit Trails: Conduct regular audits of S3 bucket policies, access logs, and permission configurations to ensure they are in line with security best practices. This assists in detecting and correcting any misconfigurations or unauthorised access attempts.
f. Secure Access Control: Use signed URLs or cookies to allow time-limited access to objects in S3 buckets. This ensures secure access to select resources while protecting sensitive credentials.
g. Cross-Origin Resource Sharing (CORS): Use CORS configurations to specify which domains can access resources in your S3 bucket. This helps to avoid cross-origin attacks.