Windows Defender Disabled via DisableAntiSpyware Registry Key

PremiumReviewedSigma · Medium · v1
Product
windows
Category
registry_set
Author
HuntRule
Published
2026-09-14
Updated
2026-09-14

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 the Windows Defender DisableAntiSpyware registry value being set, an antivirus tampering step performed by the Phorpiex downloader before deploying LockBit. Disabling Defender via this policy key removes real-time protection prior to ransomware execution.

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Malicious FIN7 AvNeutralizer EDR Killer Execution via Masqueraded Binary (via process_creation)
Suspicious Process Explorer Kernel Driver Dropped as PED.sys via File Creation (via file_event)
Windows Defender Disabled via DisableAntiSpyware Registry Key
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.