Suspicious Powershell XML Execute Command (via ps_script)

This rule detects threat actors may misuse 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

SigmamediumWindowsv1
sigma
title: Suspicious Powershell XML Execute Command (via ps_script)
id: ad4eba8d-4eb4-5600-8f23-dea64e962f8a
status: stable
description: 'This rule detects threat actors may misuse 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://attack.mitre.org/techniques/T1059/001/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1059.001/T1059.001.md#atomic-test-8---powershell-xml-requests
author: Huntrule Team
date: 2026-07-23
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:
    - Unknown
level: medium

Known false positives

  • Unknown

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