Powershell Install a DLL in System Directory — Sigma Rule

Rule metadata and linked tags

Author: frack113, Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2021-12-27 / 2024-01-22.

{
  "product": "windows",
  "category": "ps_script",
  "definition": "Requirements: Script Block Logging must be enabled"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 8251fff2a38f22eb93f2c9ade696beb1f83961f3621ccf60be30fc86b7a4ddf8

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: Powershell Install a DLL in System Directory
id: 63bf8794-9917-45bc-88dd-e1b5abc0ecfd
status: test
description: Uses PowerShell to install/copy a file into a system directory such as "System32" or "SysWOW64"
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1556.002/T1556.002.md#atomic-test-1---install-and-register-password-filter-dll
author: frack113, Nasreddine Bencherchali (Nextron Systems)
date: 2021-12-27
modified: 2024-01-22
tags:
    - attack.persistence
    - attack.credential-access
    - attack.defense-impairment
    - attack.t1556.002
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|re: '(Copy-Item|cpi) .{2,128} -Destination .{1,32}\\Windows\\(System32|SysWOW64)'
    condition: selection
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1556.002/T1556.002.md#atomic-test-1---install-and-register-password-filter-dll