Windows remote PowerShell session activity via wsmprovhost.exe process relationships

Alerts when wsmprovhost.exe is seen as a process or parent process, indicating remote PowerShell via WinRM.

FreeUnreviewedSigmamediumv1

windows-remote-powershell-session-activity-via-wsmprovhost-exe-process-relations-734f8d9b

title: Windows remote PowerShell session activity via wsmprovhost.exe process relationships
id: bae07d31-c739-4bd2-a9e3-6ecb8adac3bf
status: test
description: This rule flags process creation where wsmprovhost.exe appears either as the executing image or as the parent process image. wsmprovhost.exe is the WinRM host component used to support remote PowerShell sessions, so its presence in the process chain indicates an active remote PowerShell execution context. It relies on Windows process creation telemetry, specifically the image and parent image paths ending with wsmprovhost.exe.
references:
  - https://threathunterplaybook.com/hunts/windows/190511-RemotePwshExecution/notebook.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_winrm_remote_powershell_session_process.yml
author: Roberto Rodriguez @Cyb3rWard0g, Huntrule Team
date: 2019-09-12
modified: 2022-10-09
tags:
  - attack.execution
  - attack.lateral-movement
  - attack.t1059.001
  - attack.t1021.006
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    - Image|endswith: \wsmprovhost.exe
    - ParentImage|endswith: \wsmprovhost.exe
  condition: selection
falsepositives:
  - Legitimate usage of remote Powershell, e.g. for monitoring purposes.
level: medium
license: DRL-1.1
related:
  - id: 734f8d9b-42b8-41b2-bcf5-abaf49d5a3c8
    type: derived

What it detects

This rule flags process creation where wsmprovhost.exe appears either as the executing image or as the parent process image. wsmprovhost.exe is the WinRM host component used to support remote PowerShell sessions, so its presence in the process chain indicates an active remote PowerShell execution context. It relies on Windows process creation telemetry, specifically the image and parent image paths ending with wsmprovhost.exe.

Known false positives

Legitimate usage of remote Powershell, e.g. for monitoring purposes.

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.