AWS CloudTrail Log Evasion
Identifies the evasion of cloudtrail logging for IAM actions involving policy creation, modification or attachment. When making certain policy-related API calls, an adversary may pad the associated policy document…
Description
Identifies the evasion of cloudtrail logging for IAM actions involving policy creation, modification or attachment. When making certain policy-related API calls, an adversary may pad the associated policy document with whitespaces to trigger CloudTrail’s logging size constraints, resulting in incomplete logging where critical details about the policy are omitted. By exploiting this gap, threat actors can bypass monitoring performed through CloudTrail and can effectively obscure unauthorized changes. This rule looks for IAM API calls with the requestParameters property containing reason:”requestParameters too large” and omitted:true.
Detection logic
Its licence does not clear it for publishing here
Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.
Detection requirements
- Platform
- ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteSaaSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- event_index
Known benign triggers
- There is no known legitimate reason for padding policies with white spaces to the extent it would take to trigger Cloudtrail's logging constraints. Any instance of this should be investigated.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| permiso.io/blog/cloudtrail-logging-evasion-where-policy-size-matters | Only this detection cites it |
From the source
- At source
- Open at source
- Upstream identifier
- 9ebd48ac-a0e2-430a-a219-fe072a50146b
- Tagged by the source as
- Data Source: Amazon Web ServicesData Source: AWSData Source: AWS CloudTrailData Source: AWS IAMDomain: CloudNoise: LowPerformance: FastPlatform: AWSResources: Investigation GuideRule Type: Custom Query (KQL)Service: AWS IAMTactic: Defense EvasionUse Case: Log Auditing
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 3