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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.

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