Suspicious STS AssumeRole With Exfil Session Name via CloudTrail (via cloudtrail)

PremiumReviewedSigma · High · v1
Product
aws
Service
cloudtrail
Author
HuntRule
Published
2026-07-15
Updated
2026-08-28

ATT&CK techniques

Initial Access → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Execution

  4. Cred Access

  5. Discovery

  6. Lateral Movement

  7. Collection

  8. C2

  9. Exfiltration

  10. Impact

What it detects

This rule detects the Shai Hulud actor assuming high privilege roles using session names that begin with exfil such as exfil, exfil10 and exfil12 to run Systems Manager commands and read data. Operator chosen session names that reveal exfiltration intent are a strong hunting signal. These sessions preceded Redshift data theft.

Related detections9 linkedT1078.004 — drag to rearrange
Possible Credential Stuffing Blocked by Conditional Access in Microsoft 365
Suspicious SES Account Sending Enablement and Identity Verification via CloudTrail
Possible Stolen AWS Credential Validation via STS GetCallerIdentity
Suspicious AWS Federated Console Login From Programmatic Credentials
Suspicious M365 Legacy Authentication via BAV2ROPC Client via m365
Suspicious AWS Console Login Without MFA
Suspicious Cloud Sign-In From an Anonymizer or High-Risk Session (via signinlogs)
Suspicious Entra Sign-In to OfficeHome with axios User Agent
Suspicious AWS STS Session Token and Role Chaining Abuse via CloudTrail (via aws)
Suspicious STS AssumeRole With Exfil Session Name via CloudTrail (via cloudtrail)
Pivot detection · T1078.004 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.