Potential Winnti Dropper Activity — Sigma Rule

Rule metadata and linked tags

Author: Alexander Rausch. Source status: test; severity: high. Source dates: 2020-06-24 / 2023-01-05.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 97b9fff6058e3a798efea2a9c4ab85eabed97cd2753b74bb256d4d9db8d3caa5

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: Potential Winnti Dropper Activity
id: 130c9e58-28ac-4f83-8574-0a4cc913b97e
status: test
description: Detects files dropped by Winnti as described in RedMimicry Winnti playbook
references:
    - https://redmimicry.com/posts/redmimicry-winnti/#dropper
author: Alexander Rausch
date: 2020-06-24
modified: 2023-01-05
tags:
    - attack.stealth
    - attack.t1027
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith:
            - '\gthread-3.6.dll'
            - '\sigcmm-2.4.dll'
            - '\Windows\Temp\tmp.bat'
    condition: selection
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://redmimicry.com/posts/redmimicry-winnti/#dropper