Windows Suspicious Defender Engine or Signature Files Created
Detects Windows Defender engine (mpengine.dll) or signature database files (*.vdm) being created by any process that is not a Windows Defender component. BlueHammer extracts these files from the downloaded mpam-fe…
Description
Detects Windows Defender engine (mpengine.dll) or signature database files (*.vdm) being created by any process that is not a Windows Defender component. BlueHammer extracts these files from the downloaded mpam-fe update package into a UUID-named subdirectory of %TEMP% as part of staging the TOCTOU privilege escalation.
Detection logic
Detection requirements
- Platform
- ContainersLinuxmacOSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- sysmon_eventid_11
Known benign triggers
- Some legitimate software updates or security tools may create Windows Defender engine or signature files in user temp folders during scanning or updating processes. Filter detections for trusted update utilities and system maintenance tasks.
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/Nightmare-Eclipse/BlueHammer | 6 |
From the source
- At source
- Open at source
- Upstream identifier
- 42e848eb-1d5f-4ffb-88c2-088c4a6fdfb3
- Tagged by the source as
- BlueHammerWindows Privilege EscalationEndpointendpointSplunk 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