Potentially Suspicious Child Processes Spawned by ConHost


Description

Detects suspicious child processes related to Windows Shell utilities spawned by conhost.exe, which could indicate malicious activity using trusted system components.

Query · sigma

selection_parent:
  ParentImage|endswith: \conhost.exe
selection_child:
- Image|endswith:
  - \cmd.exe
  - \cscript.exe
  - \mshta.exe
  - \powershell_ise.exe
  - \powershell.exe
  - \pwsh.exe
  - \regsvr32.exe
  - \wscript.exe
- OriginalFileName:
  - cmd.exe
  - cscript.exe
  - mshta.exe
  - powershell_ise.exe
  - powershell.exe
  - pwsh.dll
  - regsvr32.exe
  - wscript.exe
condition: all of selection_*

Known false positives

  • Legitimate administrative tasks using `conhost.exe` to spawn child processes such as `cmd.exe`, `powershell.exe`, or `regsvr32.exe`.
Raw source Potentially Suspicious Child Processes Spawned by ConHost · Sigma
Esc
Published by SigmaHQ/sigma ↗, licensed under Detection Rule License 1.1 ↗. Reproduced here unmodified.
title: Potentially Suspicious Child Processes Spawned by ConHost
id: dfa03a09-8b92-4d83-8e74-f72839b1c407
related:
    - id: 7dc2dedd-7603-461a-bc13-15803d132355
      type: similar
status: experimental
description: Detects suspicious child processes related to Windows Shell utilities spawned by `conhost.exe`, which could indicate malicious activity using trusted system components.
references:
    - https://tria.ge/241015-l98snsyeje/behavioral2
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-02-05
tags:
    - attack.stealth
    - attack.t1202
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection_parent:
        ParentImage|endswith: '\conhost.exe'
    selection_child:
        - Image|endswith:
              - '\cmd.exe'             # Windows Command Prompt
              - '\cscript.exe'         # Windows Script Host (used for scripting exploits)
              - '\mshta.exe'           # MSHTA (HTML Application Host, often abused)
              - '\powershell_ise.exe'  # PowerShell ISE
              - '\powershell.exe'      # Windows PowerShell
              - '\pwsh.exe'            # PowerShell Core
              - '\regsvr32.exe'        # Windows Registry Server (commonly used for exploits)
              - '\wscript.exe'         # Windows Script Host (for executing scripts)
        - OriginalFileName:
              - 'cmd.exe'
              - 'cscript.exe'
              - 'mshta.exe'
              - 'powershell_ise.exe'
              - 'powershell.exe'
              - 'pwsh.dll'
              - 'regsvr32.exe'
              - 'wscript.exe'
    condition: all of selection_*
falsepositives:
    - Legitimate administrative tasks using `conhost.exe` to spawn child processes such as `cmd.exe`, `powershell.exe`, or `regsvr32.exe`.
level: high

Detection rules belong to the projects that publish them and remain under their own licenses. This site indexes and links to them; it claims no rights in them.