SigmaHQ/rules/windows/builtin/win_susp_mshta_execution.yml

title: MSHTA Suspicious Execution 01
id: cc7abbd0-762b-41e3-8a26-57ad50d2eea3
status: experimental
description: Detection for mshta.exe suspicious execution patterns sometimes involving file polyglotism
date: 22/02/2019
modified: 22/02/2019
author: Diego Perez (@darkquassar)
references:
    - http://blog.sevagas.com/?Hacking-around-HTA-files
    - https://0x00sec.org/t/clientside-exploitation-in-2018-how-pentesting-has-changed/7356
    - https://docs.microsoft.com/en-us/dotnet/standard/data/xml/xslt-stylesheet-scripting-using-msxsl-script
    - https://medium.com/tsscyber/pentesting-and-hta-bypassing-powershell-constrained-language-mode-53a42856c997
tags:
    - attack.defense_evasion
    - attack.t1140
logsource:
    category: process_creation
    product: windows
falsepositives: 
    - False positives depend on scripts and administrative tools used in the monitored environment
level: high
detection:
    selection1:
        CommandLine: 
            - '*mshta vbscript:CreateObject("Wscript.Shell")*'
            - '*mshta vbscript:Execute("Execute*'
            - '*mshta vbscript:CreateObject("Wscript.Shell").Run("mshta.exe*'
    selection2:
        Image:
            - 'C:\Windows\system32\mshta.exe'
        CommandLine: 
            - '*.jpg*'
            - '*.png*'
            - '*.lnk*'
            # - '*.chm*'  # could be prone to false positives
            - '*.xls*'
            - '*.doc*'
            - '*.zip*'
    condition:
        selection1 or selection2