Sigma rule: PPL Tampering Via WerFaultSecure

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-346e3f6616b8, updated 2025-11-23T00:00:00.000Z.

Rule

Title: PPL Tampering Via WerFaultSecure
Status: experimental
Level: high
Author: Jason (https://github.com/0xbcf)
Date: 2025-09-23
Modified: 2025-11-23
File: rules/windows/process_creation/proc_creation_win_werfaultsecure_abuse.yml
Commit: ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potential abuse of WerFaultSecure.exe to dump Protected Process Light (PPL) processes like LSASS or to freeze security solutions (EDR/antivirus).
This technique is used by tools such as EDR-Freeze and WSASS to bypass PPL protections and access sensitive information or disable security software.
Distinct command line patterns help identify the specific tool:
- WSASS usage typically shows: "WSASS.exe WerFaultSecure.exe [PID]" in ParentCommandLine
- EDR-Freeze usage typically shows: "EDR-Freeze_[version].exe [PID] [timeout]" in ParentCommandLine
Legitimate debugging operations using WerFaultSecure are rare in production environments and should be investigated.

Log source

product: windows
category: process_creation

Detection

selection_image:
    - Image|endswith: '\WerFaultSecure.exe'
    - OriginalFileName: 'WerFaultSecure.exe'
selection_args:
    CommandLine|contains|all:
        - ' /h '
        - ' /pid ' # Antimalware or EDR process pid will be after this flag
        - ' /tid '
        - ' /encfile '
        - ' /cancel '
        - ' /type '
        - ' 268310'
condition: all of selection_*

False positives (as the rule lists them)

Legitimate usage of WerFaultSecure for debugging purposes

MITRE ATT&CK ids this rule names

Related rules

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_werfaultsecure_abuse.yml

Sources and licences

SigmaHQ
"PPL Tampering Via WerFaultSecure" by Jason (https://github.com/0xbcf) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_werfaultsecure_abuse.yml.
Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License
Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: PPL Tampering Via WerFaultSecure",
entity page, dataset version ref-346e3f6616b8, updated 2025-11-23T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/1f0b4cac-9c81-41f4-95d0-8475ff46b3e2 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 1f0b4cac-9c81-41f4-95d0-8475ff46b3e2, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.