Windows Impair Defense Disable Win Defender Compute File Hashes
The following analytic detects modifications to the Windows registry that disable Windows Defender's file hash computation by setting the EnableFileHashComputation value to 0. This detection leverages data from the…
Description
The following analytic detects modifications to the Windows registry that disable Windows Defender's file hash computation by setting the EnableFileHashComputation value to 0. This detection leverages data from the Endpoint.Registry data model, focusing on changes to the specific registry path associated with Windows Defender. Disabling file hash computation can significantly impair Windows Defender's ability to detect and scan for malware, making it a critical behavior to monitor. If confirmed malicious, this activity could allow attackers to bypass Windows Defender, facilitating undetected malware execution and persistence in the environment.
Detection logic
Detection requirements
- Platform
- ContainersESXiIaaSLinuxmacOSNetwork DevicesWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- sysmon_eventid_13
Known benign triggers
- It is unusual to turn this feature off a Windows system since it is a default security control, although it is not rare for some policies to disable it. Although no false positives have been identified, use the provided filter macro to tune the search.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| github.com/undergroundwires/privacy.sexy | 22 |
| x.com/malmoeb/status/1742604217989415386?s=20 | 22 |
From the source
- At source
- Open at source
- Upstream identifier
- fe52c280-98bd-4596-b6f6-a13bbf8ac7c6
- Tagged by the source as
- Windows Defense Evasion TacticsWindows Registry AbuseEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1