Windows conhost.exe Spawned by Uncommon Parent Process

title: Windows conhost.exe Spawned by Uncommon Parent Process
id: 95608482-93ab-4310-ae65-93a0271e5253
status: test
description: This rule identifies instances where conhost.exe is created by a parent process that is not among a predefined set of common Windows parents. Suspicious conhost.exe ancestry can indicate abnormal process interactions often used during code execution or manipulation of console behavior. It relies on process creation telemetry, specifically the conhost.exe image name and its parent image/command-line details to suppress known benign parent contexts.
references:
  - https://www.elastic.co/guide/en/security/current/conhost-spawned-by-suspicious-parent-process.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_conhost_uncommon_parent.yml
author: Tim Rauch, Elastic (idea), Huntrule Team
date: 2022-09-28
modified: 2025-03-06
tags:
  - attack.execution
  - attack.t1059
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith: \conhost.exe
    ParentImage|endswith:
      - \explorer.exe
      - \lsass.exe
      - \regsvr32.exe
      - \rundll32.exe
      - \services.exe
      - \smss.exe
      - \spoolsv.exe
      - \svchost.exe
      - \userinit.exe
      - \wininit.exe
      - \winlogon.exe
  filter_main_svchost:
    ParentCommandLine|contains:
      - -k apphost -s AppHostSvc
      - -k imgsvc
      - -k localService -p -s RemoteRegistry
      - -k LocalSystemNetworkRestricted -p -s NgcSvc
      - -k NetSvcs -p -s NcaSvc
      - -k netsvcs -p -s NetSetupSvc
      - -k netsvcs -p -s wlidsvc
      - -k NetworkService -p -s DoSvc
      - -k wsappx -p -s AppXSvc
      - -k wsappx -p -s ClipSVC
      - -k wusvcs -p -s WaaSMedicSvc
  filter_optional_dropbox:
    ParentCommandLine|contains:
      - C:\Program Files (x86)\Dropbox\Client\
      - C:\Program Files\Dropbox\Client\
  condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: cbb9e3d1-2386-4e59-912e-62f1484f7a89
    type: derived