Suspicious Powershell MsXml COM Object (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 MsXml COM Object (via ps_script)
id: 5fe11bf7-3138-598d-8d8d-0e50702d8c6f
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-7---powershell-msxml-com-object---with-prompt
    - https://learn.microsoft.com/en-us/previous-versions/windows/desktop/ms766431(v=vs.85)
    - https://www.trendmicro.com/en_id/research/22/e/uncovering-a-kingminer-botnet-attack-using-trend-micro-managed-x.html
author: Huntrule Team
date: 2026-07-02
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains|all:
            - 'New-Object'
            - '-ComObject'
            - 'MsXml2.'
            - 'XmlHttp'
    condition: 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.