Malicious Windows Defender Exclusion for Windows Dell Folder

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-08-25
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 Add-MpPreference adding a Defender exclusion path for a Dell folder under the Windows directory, a Prometei defense-evasion step. The botnet staged modules such as its Mimikatz variant in C:\Windows\Dell and excluded that path from Defender scanning. A Defender exclusion for a non-standard folder inside the Windows directory strongly indicates malware hiding its working directory.

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In-Memory AMSI or ETW Bypass in PowerShell (via process_creation)
Malicious Microsoft Defender Critical Security Components Disabled - Command (via process_creation)
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Malicious Windows Defender Exclusion for Windows Dell Folder
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.