Windows PowerShell Execution via EngineVersion/HostVersion Mismatch in Command Start Telemetry

Detects PowerShell execution attempts that match a specific executable EngineVersion/HostVersion mismatch pattern on Windows.

FreeReviewedSigma · High · v2

Product: windows
Category: ps_classic_start
Author: Sean Metcalf (source), Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2017-03-05
Updated: 2026-07-31

Analysis Detection

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies PowerShell being launched where telemetry shows a mismatch between the PowerShell engine version and the host version. Attackers may use this behavior to run PowerShell in contexts where version handling differs from expectations, potentially helping execution proceed with less scrutiny. Detection relies on PowerShell classic start telemetry fields containing specific EngineVersion and HostVersion substrings.

Reporting behind it

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Windows PowerShell Execution via EngineVersion/HostVersion Mismatch in Command Start Telemetry

Pivot detection · T1059.001 · 9 related

Changelog

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

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

windows-powershell-launch-triggered-via-executable-version-mismatch-c70e019b

title: Windows PowerShell Execution via EngineVersion/HostVersion Mismatch in Command Start Telemetry
id: 8281ebd2-2751-4800-bb2f-ef579204ea2a
status: test
description: This rule identifies PowerShell being launched where telemetry shows a mismatch between the PowerShell engine version and the host version. Attackers may use this behavior to run PowerShell in contexts where version handling differs from expectations, potentially helping execution proceed with less scrutiny. Detection relies on PowerShell classic start telemetry fields containing specific EngineVersion and HostVersion substrings.
references:
  - https://adsecurity.org/?p=2921
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_classic/posh_pc_exe_calling_ps.yml
author: Sean Metcalf (source), Florian Roth (Nextron Systems), Huntrule Team
date: 2017-03-05
modified: 2023-10-27
tags:
  - attack.execution
  - attack.t1059.001
logsource:
  product: windows
  category: ps_classic_start
detection:
  selection_engine:
    Data|contains:
      - EngineVersion=2.
      - EngineVersion=4.
      - EngineVersion=5.
  selection_host:
    Data|contains: HostVersion=3.
  condition: all of selection_*
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: c70e019b-1479-4b65-b0cc-cd0c6093a599
    type: derived

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