Powershell XML Execute Command — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: medium. Source dates: 2022-01-19 / 2023-01-19.

{
  "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: 14b5cb6d48b3e4627de5f628850fc97824d1c6a34fecee3331c861c91570d3f2

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 XML Execute Command
id: 6c6c6282-7671-4fe9-a0ce-a2dcebdc342b
status: test
description: |
    Adversaries may abuse PowerShell commands and scripts for execution.
    PowerShell is a powerful interactive command-line interface and scripting environment included in the Windows operating system. (Citation: TechNet PowerShell)
    Adversaries can use PowerShell to perform a number of actions, including discovery of information and execution of code
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1059.001/T1059.001.md#atomic-test-8---powershell-xml-requests
author: frack113
date: 2022-01-19
modified: 2023-01-19
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_xml:
        ScriptBlockText|contains|all:
            - 'New-Object'
            - 'System.Xml.XmlDocument'
            - '.Load'
    selection_exec:
        ScriptBlockText|contains:
            - 'IEX '
            - 'Invoke-Expression '
            - 'Invoke-Command '
            - 'ICM -'
    condition: all of selection_*
falsepositives:
    - Legitimate administrative script
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate administrative script

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1059.001/T1059.001.md#atomic-test-8---powershell-xml-requests