PowerShell ScriptBlock Obfuscation via MSHTA VBScript CreateObject Execution

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies PowerShell script block content that includes multiple MSHTA and VBScript execution indicators in the same block, suggesting obfuscated or staged execution. Attackers often use MSHTA with VBScript to launch processes while hiding intent within scripted content. The detection relies on Script Block Logging telemetry by matching specific string combinations within ScriptBlockText.

Reporting behind it

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PowerShell ScriptBlock Obfuscation via MSHTA VBScript CreateObject Execution

Pivot detection · T1027 · 9 related

Changelog

v2

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.

powershell-script-obfuscation-via-mshta-and-vbscript-url-execution-e55a5195

title: PowerShell ScriptBlock Obfuscation via MSHTA VBScript CreateObject Execution
id: f86282e7-e5ed-432b-9fc5-6117e4001317
status: test
description: This rule identifies PowerShell script block content that includes multiple MSHTA and VBScript execution indicators in the same block, suggesting obfuscated or staged execution. Attackers often use MSHTA with VBScript to launch processes while hiding intent within scripted content. The detection relies on Script Block Logging telemetry by matching specific string combinations within ScriptBlockText.
references:
  - https://github.com/SigmaHQ/sigma/issues/1009
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_invoke_obfuscation_via_use_mhsta.yml
author: Nikita Nazarov, oscd.community, Huntrule Team
date: 2020-10-08
modified: 2022-11-29
tags:
  - attack.stealth
  - attack.t1027
  - attack.execution
  - attack.t1059.001
logsource:
  product: windows
  category: ps_script
  definition: "Requirements: Script Block Logging must be enabled"
detection:
  selection_4104:
    ScriptBlockText|contains|all:
      - set
      - "&&"
      - mshta
      - vbscript:createobject
      - .run
      - (window.close)
  condition: selection_4104
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: e55a5195-4724-480e-a77e-3ebe64bd3759
    type: derived

Convert

This rule as a query you can run. Uses no unlock credit.

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