Hidden Powershell in Link File Pattern — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: medium. Source dates: 2022-02-06 / not supplied.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: c21b466ed575d7c97b32f1f4eef6e42d652d63302f81b6357d9ba78f71dd42d4

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Hidden Powershell in Link File Pattern
id: 30e92f50-bb5a-4884-98b5-d20aa80f3d7a
status: test
description: Detects events that appear when a user click on a link file with a powershell command in it
references:
    - https://www.x86matthew.com/view_post?id=embed_exe_lnk
author: frack113
date: 2022-02-06
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage: C:\Windows\explorer.exe
        Image: C:\Windows\System32\cmd.exe
        CommandLine|contains|all:
            - 'powershell'
            - '.lnk'
    condition: selection
falsepositives:
    - Legitimate commands in .lnk files
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate commands in .lnk files

Source references

• https://www.x86matthew.com/view_post?id=embed_exe_lnk