Windows Fake wermgr.exe Execution via Renamed cmd/powershell/powershell_ise

Detects disguised execution of cmd or PowerShell by matching original file name with a wermgr.exe process image.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-08-23
Updated
2026-07-31
title: Windows Fake wermgr.exe Execution via Renamed cmd/powershell/powershell_ise
id: 2f15916b-dc2b-44bd-9cf2-42381f2b31a0
status: test
description: This rule identifies process execution where the image filename ends with \wermgr.exe while the process reports an OriginalFileName of cmd.exe, powershell.exe, or powershell_ise.exe. This pattern is consistent with attackers renaming legitimate Windows binaries to masquerade as wermgr.exe during exploitation activity. Detection relies on Windows process creation telemetry that includes both the executable path/name and the OriginalFileName metadata.
references:
  - https://github.com/Wh04m1001/CVE-2023-36874
  - https://www.crowdstrike.com/blog/falcon-complete-zero-day-exploit-cve-2023-36874/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Exploits/CVE-2023-36874/proc_creation_win_exploit_cve_2023_36874_fake_wermgr.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-08-23
tags:
  - attack.execution
  - cve.2023-36874
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    OriginalFileName:
      - Cmd.Exe
      - powershell_ise.EXE
      - powershell.exe
    Image|endswith: \wermgr.exe
  condition: selection
falsepositives:
  - Unlikely
level: high
license: DRL-1.1
related:
  - id: 50dbc08b-60ce-40f1-a6b6-346497e34c88
    type: derived