huntrule

Windows Security 4697 PowerShell obfuscated content using COMPRESS OBFUSCATION components

Alerts on service creation events where the ServiceFileName includes PowerShell obfuscation patterns tied to compression stream and ASCII encoding.

FreeReviewedSigma · Medium · v2
Product
windows
Service
security
Author
Timur Zinniatullin, oscd.community (SigmaHQ), DRL 1.1
Published
2020-10-18
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Execution → Defense Evasion

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags Windows System Security audit events (EventID 4697) where the service binary name indicates PowerShell use of specific obfuscation-related .NET patterns. Attackers may compress and obfuscate PowerShell script content to hinder inspection and detection. The detection relies on Security log telemetry for EventID 4697 and matching string patterns within the logged ServiceFileName.

Reporting behind it

Related detections9 linkedT1027 — drag to rearrange
Suspicious PowerShell Invoke-Expression with Replace Obfuscation
Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell
Suspicious Python Interpreter Launching Encoded PowerShell via subprocess
Suspicious PS1Bot PowerShell Payload Written to ProgramData (via file_event)
Malicious Non-Interactive Encoded PowerShell Stager (via process_creation)
Suspicious Hidden PowerShell Executing Substring of Dropped File
PowerShell Encoded or Download-Cradle Command Line (via process_creation)
Obfuscated Encoded PowerShell Payload Deployed - PowerShell (via powershell)
Suspicious PowerShell AES Decryption and Reflective Method Invocation in SolarMarker
Windows Security 4697 PowerShell obfuscated content using COMPRESS OBFUSCATION components
Pivot detection · T1027 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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