Windows ChromeLoader Execution via Scheduled Task and Hidden PowerShell Launch

Flags PowerShell-launched chrome.exe that uses --load-extension from local AppData Chrome paths for ChromeLoader-style execution.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
@kostastsale (SigmaHQ), DRL 1.1
Published
2022-01-10
Updated
2026-07-31
title: Windows ChromeLoader Execution via Scheduled Task and Hidden PowerShell Launch
id: e1797b36-ca61-4d21-80e4-5b49c999f7af
status: test
description: This rule matches process creation where a chrome.exe child process is launched and the parent process is powershell.exe executing with an execution policy bypass and hidden window parameters. It also requires the PowerShell command line to include a specific Chrome extension loading argument pointing to the AppData local chrome directory. This behavior is relevant because attackers can use scheduled-task-driven PowerShell to run a staged loader that triggers Chrome to execute malicious extensions; the rule relies on Windows process creation telemetry including Image, ParentImage, ParentCommandLine, and CommandLine.
references:
  - https://github.com/xephora/Threat-Remediation-Scripts/tree/main/Threat-Track/CS_INSTALLER
  - https://twitter.com/th3_protoCOL/status/1480621526764322817
  - https://twitter.com/Kostastsale/status/1480716528421011458
  - https://www.virustotal.com/gui/file/ded20df574b843aaa3c8e977c2040e1498ae17c12924a19868df5b12dee6dfdd
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2022/Malware/ChromeLoader/proc_creation_win_malware_chrome_loader_execution.yml
author: "@kostastsale, Huntrule Team"
date: 2022-01-10
tags:
  - attack.privilege-escalation
  - attack.execution
  - attack.persistence
  - attack.t1053.005
  - attack.t1059.001
  - attack.t1176
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    ParentImage|endswith: \powershell.exe
    ParentCommandLine|contains: -ExecutionPolicy Bypass -WindowStyle Hidden -E JAB
    CommandLine|contains: --load-extension="*\Appdata\local\chrome"
    Image|endswith: \chrome.exe
  condition: selection
falsepositives:
  - Unlikely
level: high
license: DRL-1.1
related:
  - id: 0a74c5a9-1b71-4475-9af2-7829d320d5c2
    type: derived