Suspicious Path In Keyboard Layout IME File Registry Value — Sigma Rule

Rule metadata and linked tags

Author: X__Junior (Nextron Systems). Source status: test; severity: high. Source dates: 2023-11-21 / not supplied.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 161937b72bff67d60a9f4df98e1e80593c9e6fef9e1ff2f65d0b9b4b58b475c5

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 Path In Keyboard Layout IME File Registry Value
id: 9d8f9bb8-01af-4e15-a3a2-349071530530
related:
    - id: b888e3f2-224d-4435-b00b-9dd66e9ea1f1
      type: derived
status: test
description: |
    Detects usage of Windows Input Method Editor (IME) keyboard layout feature, which allows an attacker to load a DLL into the process after sending the WM_INPUTLANGCHANGEREQUEST message.
    Before doing this, the client needs to register the DLL in a special registry key that is assumed to implement this keyboard layout. This registry key should store a value named "Ime File" with a DLL path.
    IMEs are essential for languages that have more characters than can be represented on a standard keyboard, such as Chinese, Japanese, and Korean.
references:
    - https://www.linkedin.com/pulse/guntior-story-advanced-bootkit-doesnt-rely-windows-disk-baranov-wue8e/
author: X__Junior (Nextron Systems)
date: 2023-11-21
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: windows
    category: registry_set
detection:
    selection_registry:
        TargetObject|contains|all:
            - '\Control\Keyboard Layouts\'
            - 'Ime File'
    selection_folders_1:
        Details|contains:
            - ':\Perflogs\'
            - ':\Users\Public\'
            - ':\Windows\Temp\'
            - '\AppData\Local\Temp\'
            - '\AppData\Roaming\'
            - '\Temporary Internet'
    selection_folders_2:
        - Details|contains|all:
              - ':\Users\'
              - '\Favorites\'
        - Details|contains|all:
              - ':\Users\'
              - '\Favourites\'
        - Details|contains|all:
              - ':\Users\'
              - '\Contacts\'
    condition: selection_registry and 1 of selection_folders_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://www.linkedin.com/pulse/guntior-story-advanced-bootkit-doesnt-rely-windows-disk-baranov-wue8e/