Suspicious Process Access of MsMpEng by WerFaultSecure - EDR-Freeze
Detects process access events where WerFaultSecure accesses MsMpEng.exe with dbgcore.dll or dbghelp.dll in the call trace, indicating potential EDR freeze techniques. This technique leverages WerFaultSecure.exe…
Description
Detects process access events where WerFaultSecure accesses MsMpEng.exe with dbgcore.dll or dbghelp.dll in the call trace, indicating potential EDR freeze techniques. This technique leverages WerFaultSecure.exe running as a Protected Process Light (PPL) with WinTCB protection level to call MiniDumpWriteDump and suspend EDR/AV processes, allowing malicious activity to execute undetected during the suspension period.
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 product
- windows
- Log source category
- process_access
Known benign triggers
- Legitimate Windows Error Reporting operations
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 |
|---|---|
| blog.axelarator.net/hunting-for-edr-freeze/ | 2 |
From the source
- At source
- Open at source
- Upstream identifier
- 387df17d-3b04-448f-8669-9e7fd5e5fd8c
- Tagged by the source as
- attack.defense-impairment
Licence
- Published under
- Detection Rule License 1.1Read the licence
- Attribution
- Required
Authorship
- Published
- Aug 26, 2026
- Version
- 1