Suspicious Defender Exclusion for Public Controller Path (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-06-30
Updated
2026-08-28

ATT&CK techniques

  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 detects PowerShell adding a Microsoft Defender exclusion for a Controller folder under C:\Users\Public as done by the Efimer Trojan to protect its payload. Whitelisting an attacker-controlled directory in a world-writable location lets the malware run and update without being scanned. This combination of Add-MpPreference and a public path is rarely legitimate.

Related detections9 linkedT1685 — drag to rearrange
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Suspicious ESXi Management Agent Stop via vpxa init Script (via process_creation)
Malicious ESXi Firewall Disable via esxcli (via process_creation)
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Suspicious Windows Defender Exclusion Enumeration via reg query (via process_creation)
Malicious Windows Defender Exclusion Added via PowerShell (via process_creation)
Malicious BYOVD EDR Kill via Renamed GMER Driver by Agonizing Serpens
Suspicious Defender Exclusion for Public Controller Path (via process_creation)
Pivot detection · T1685 · 9 related

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