Possible Suspicious PowerShell Keywords (via ps_script)

This rule detects potentially anomalous keywords that could indicate the use of a PowerShell exploitation framework

SigmamediumWindowsv1
sigma
title: Possible Suspicious PowerShell Keywords (via ps_script)
id: 18eb1af5-523d-58e7-a76b-0852aff59a54
status: stable
description: This rule detects potentially anomalous keywords that could indicate the use of a PowerShell exploitation framework
references:
    - https://attack.mitre.org/techniques/T1059/001/
    - https://posts.specterops.io/entering-a-covenant-net-command-and-control-e11038bcf462
    - https://github.com/PowerShellMafia/PowerSploit/blob/d943001a7defb5e0d1657085a77a0e78609be58f/CodeExecution/Invoke-ReflectivePEInjection.ps1
    - https://github.com/hlldz/Phant0m/blob/30c2935d8cf4aafda17ee2fab7cd0c4aa9a607c2/old/Invoke-Phant0m.ps1
    - https://gist.github.com/MHaggis/0dbe00ad401daa7137c81c99c268cfb7
author: Huntrule Team
date: 2026-01-05
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains:
            - 'System.Reflection.Assembly.Load($'
            - '[System.Reflection.Assembly]::Load($'
            - '[Reflection.Assembly]::Load($'
            - 'System.Reflection.AssemblyName'
            - 'Reflection.Emit.AssemblyBuilderAccess'
            - 'Reflection.Emit.CustomAttributeBuilder'
            - 'Runtime.InteropServices.UnmanagedType'
            - 'Runtime.InteropServices.DllImportAttribute'
            - 'SuspendThread'
            - 'rundll32'
    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.