huntrule

Windows: reg.exe Adds Windows Defender Exclusion Paths via Registry Value Update

Detects reg.exe commands that modify Windows Defender/Microsoft Antimalware exclusion path registry entries.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
frack113 (SigmaHQ), DRL 1.1
Published
2022-02-13
Updated
2026-07-30
AnalysisDetection

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 flags process executions of reg.exe where the command line targets Defender/Microsoft Antimalware exclusion paths and sets a registry value matching ADD /t REG_DWORD /v /d 0. Attackers can use Defender exclusions to reduce security visibility by preventing scanning of specific directories. The detection relies on Windows process creation telemetry, matching reg.exe invocation and specific registry path and command-line parameters.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange
Suspicious Vulnerable Intel Ethernet Driver Load for BYOVD via SCATTERED SPIDER (via driver_load)
Malicious Defender Disable And Executable Exclusion Via Registry
Malicious UAC Disable via EnableLUA Registry Modification (via registry_set)
Malicious AMSI and ETW Patching via PowerShell Script
Malicious PowMix AMSI Bypass via amsiInitFailed
Suspicious ThrottleStop Driver Abuse for Defense Evasion in Ransomware Attacks
Malicious Disabling of Microsoft Defender Real-Time Protection via SystemSettingsAdminFlows by DeadLock Ransomware
Suspicious Security Software Uninstallation via WMIC Product Call Uninstall (Chaos Ransomware)
Suspicious Security Product Uninstall via wmic product call uninstall
Windows: reg.exe Adds Windows Defender Exclusion Paths via Registry Value Update
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.