huntrule

Windows Security: Detect Obfuscated PowerShell IEX Invocation via ServiceFileName Patterns (Event ID 4697)

Alerts on EventID 4697 instances where ServiceFileName matches obfuscated IEX-style PowerShell invocation patterns consistent with Invoke-Obfuscation.

FreeReviewedSigma · High · v2
Product
windows
Service
security
Author
Daniel Bohannon (@Mandiant/@FireEye), oscd.community (SigmaHQ), DRL 1.1
Published
2019-11-08
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

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 Security audit Event ID 4697 where the recorded service binary path contains specific strings consistent with obfuscated PowerShell IEX invocation patterns. Attackers commonly use obfuscation to evade command-line inspection and to hide the real payload delivery mechanism. Telemetry relies on the Security log producing Event ID 4697 along with the ServiceFileName field matching multiple predefined regular-expression patterns.

Reporting behind it

Related detections9 linkedT1027 — drag to rearrange
Suspicious PowerShell Invoke-Expression with Replace Obfuscation
Suspicious Base64 Decoded Payload Piped to Shell
Suspicious Shell Command Obfuscation via printf Escape Encoding on VMware ESXi (via process_creation)
Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell
Suspicious Python Interpreter Launching Encoded PowerShell via subprocess
Suspicious PowerShell Download Of Text-Disguised Payload
Suspicious Encrypted Implant File Creation for DLL Search Order Hijacking (RainyDay Turian PlugX)
Suspicious PS1Bot PowerShell Payload Written to ProgramData (via file_event)
Malicious Non-Interactive Encoded PowerShell Stager (via process_creation)
Windows Security: Detect Obfuscated PowerShell IEX Invocation via ServiceFileName Patterns (Event ID 4697)
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.