Suspicious JavaScript Execution Via Mshta.EXE — Sigma Rule

Rule metadata and linked tags

Author: E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community. Source status: test; severity: high. Source dates: 2019-10-24 / 2023-02-07.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ec912420cfc61a7251c61eb010a02d4e289b73168ec2d4f9b7d8ee1bc75294ce

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Suspicious JavaScript Execution Via Mshta.EXE
id: 67f113fa-e23d-4271-befa-30113b3e08b1
status: test
description: Detects execution of javascript code using "mshta.exe".
references:
    - https://eqllib.readthedocs.io/en/latest/analytics/6bc283c4-21f2-4aed-a05c-a9a3ffa95dd4.html
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1218.005/T1218.005.md
author: E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community
date: 2019-10-24
modified: 2023-02-07
tags:
    - attack.stealth
    - attack.t1218.005
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\mshta.exe'
        - OriginalFileName: 'MSHTA.EXE'
    selection_cli:
        CommandLine|contains: 'javascript'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://eqllib.readthedocs.io/en/latest/analytics/6bc283c4-21f2-4aed-a05c-a9a3ffa95dd4.html
• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1218.005/T1218.005.md