Windows PowerShell Starts Process Using Batch (.cmd/.bat) Scripts

Flags PowerShell Start-Process activity that references .bat/.cmd files, indicating batch script execution attempts.

FreeReviewedSigma · Medium · v2
Product
windows
Category
ps_script
Author
frack113 (SigmaHQ), DRL 1.1
Published
2022-01-02
Updated
2026-07-31
title: Windows PowerShell Starts Process Using Batch (.cmd/.bat) Scripts
id: b667e98f-3172-4454-adf6-cf6bcfe612b7
status: test
description: This rule identifies PowerShell script block activity where a Start-Process call is executed with references to Windows batch script extensions (.cmd or .bat). Attackers commonly use batch files to run sequences of commands through the Windows command interpreter, often to automate execution steps or stage follow-on actions. The detection relies on Script Block Logging telemetry that contains the executed PowerShell script text.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1059.003/T1059.003.md#atomic-test-1---create-and-execute-batch-script
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_susp_execute_batch_script.yml
author: frack113, Huntrule Team
date: 2022-01-02
tags:
  - attack.execution
  - attack.t1059.003
logsource:
  product: windows
  category: ps_script
  definition: "Requirements: Script Block Logging must be enabled"
detection:
  selection_start:
    ScriptBlockText|contains: Start-Process
  selection_batch:
    ScriptBlockText|contains:
      - .cmd
      - .bat
  condition: all of selection_*
falsepositives:
  - Legitimate administration script
level: medium
license: DRL-1.1
related:
  - id: b5522a23-82da-44e5-9c8b-e10ed8955f88
    type: derived