PowerShell Launch With --headless From Conhost.exe on Windows

Flags headless ConHost launching PowerShell on Windows based on process name and command-line arguments.

FreeReviewedSigma · Medium · v2
Product
windows
Category
process_creation
Author
Matt Anderson (Huntress) (SigmaHQ), DRL 1.1
Published
2024-07-23
Updated
2026-07-31
title: PowerShell Launch With --headless From Conhost.exe on Windows
id: 7e7142ca-65a1-4e16-bf3c-60409574ec94
related:
  - id: 00ca75ab-d5ce-43be-b86c-55ff39c6abfc
    type: derived
  - id: 056c7317-9a09-4bd4-9067-d051312752ea
    type: derived
status: test
description: This rule identifies Windows process creations where PowerShell is launched with the --headless flag from a headless ConHost (conhost.exe) process. Attackers may use headless console hosting to reduce user visibility and facilitate stealthy command execution. The detection relies on Windows process creation telemetry, matching conhost.exe execution context and CommandLine content containing both --headless and powershell.
references:
  - https://www.huntress.com/blog/fake-browser-updates-lead-to-boinc-volunteer-computing-software
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_conhost_headless_powershell.yml
author: Matt Anderson (Huntress), Huntrule Team
date: 2024-07-23
tags:
  - attack.execution
  - attack.stealth
  - attack.t1059.001
  - attack.t1059.003
  - attack.t1564.003
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    - Image|endswith: \conhost.exe
    - OriginalFileName: CONHOST.EXE
  selection_cli:
    CommandLine|contains|all:
      - --headless
      - powershell
  condition: all of selection_*
falsepositives:
  - Unknown
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_conhost_headless_powershell/info.yml
license: DRL-1.1