sigmamediumHunting

Add Windows Capability Via PowerShell Cmdlet

Detects usage of the "Add-WindowsCapability" cmdlet to add Windows capabilities. Notable capabilities could be "OpenSSH" and others.

Detection Query

selection_img:
  - Image|endswith:
      - \powershell.exe
      - \pwsh.exe
  - OriginalFileName:
      - PowerShell.EXE
      - pwsh.dll
selection_cmdlet:
  CommandLine|contains: Add-WindowsCapability
selection_capa:
  CommandLine|contains: OpenSSH.
condition: all of selection_*

Author

Nasreddine Bencherchali (Nextron Systems)

Created

2023-01-22

Data Sources

windowsProcess Creation Events

Platforms

windows

References

Tags

attack.execution

Raw Content

title: Add Windows Capability Via PowerShell Cmdlet
id: b36d01a3-ddaf-4804-be18-18a6247adfcd
related:
    - id: 155c7fd5-47b4-49b2-bbeb-eb4fab335429
      type: similar
status: test
description: Detects usage of the "Add-WindowsCapability" cmdlet to add Windows capabilities. Notable capabilities could be "OpenSSH" and others.
references:
    - https://learn.microsoft.com/en-us/windows-server/administration/openssh/openssh_install_firstuse?tabs=powershell
    - https://www.virustotal.com/gui/file/af1c82237b6e5a3a7cdbad82cc498d298c67845d92971bada450023d1335e267/content
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-22
modified: 2023-05-09
tags:
    - attack.execution
logsource:
    product: windows
    category: process_creation
detection:
    selection_img:
        - Image|endswith:
              - '\powershell.exe'
              - '\pwsh.exe'
        - OriginalFileName:
              - 'PowerShell.EXE'
              - 'pwsh.dll'
    selection_cmdlet:
        CommandLine|contains: 'Add-WindowsCapability'
    selection_capa:
        CommandLine|contains: 'OpenSSH.' # For both "OpenSSH.Server" and "OpenSSH.Client"
    condition: all of selection_*
falsepositives:
    - Legitimate usage of the capabilities by administrators or users. Add additional filters accordingly.
level: medium