IAM role with s3 listing and get privileges can be assumed by unexpected principals

What this check finds

The ability to list s3 buckets, and get objects from them, should be restricted largely to people as compromising an EC2 with this privilege could lead to exfiltration of data.

Passing looks like: No S3-exfil role assumable by unexpected principals.

How to fix it

Remove broad S3 List/Get permissions from roles assumable by EC2 or services, or scope the S3 permissions to specific bucket ARNs. Update the trust policy to restrict principals.

Compliance controls it is evidence for

A failing result counts against these controls in KloudLytics; a passing one is evidence towards them. How compliance mapping works

Checked on every scan

KloudLytics runs this check each time it scans a connected AWS account, through a read-only role, and lists every affected resource with its region. On Pro and Business a fix is written for the specific resource rather than the general case above. The exact access it needs

More IAM checks

• HighDeprecated or flawed AWS managed policy in use
• HighIAM role allows assumption from anywhere
• HighIAM role with admin privileges can be assumed by unexpected principals
• HighIAM user access key has not been rotated in over 180 days
• HighIncorrect policy used to attempt to enforce MFA
• HighInline policy allows privilege escalation to admin
• HighPrincipal has an attached policy granting administrative access
• MediumExpired SSL/TLS certificate stored in IAM

All IAM checks