Sigma rule: Uncommon Extension In Keyboard Layout IME File Registry Value

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-6a77b741c448, updated 2023-11-21T00:00:00.000Z.

Rule

Title
Uncommon Extension In Keyboard Layout IME File Registry Value
Status
test
Level
high
Author
X__Junior (Nextron Systems)
Date
2023-11-21
File
rules/windows/registry/registry_set/registry_set_ime_non_default_extension.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

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.

Log source

product
windows
category
registry_set

Detection

selection:
    TargetObject|contains|all:
        - '\Control\Keyboard Layouts\'
        - 'Ime File'
filter_main_known_extension:
    Details|endswith: '.ime'
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

  • IMEs are essential for languages that have more characters than can be represented on a standard keyboard, such as Chinese, Japanese, and Korean.

Tags

  • attack.defense-impairment
  • attack.t1685

MITRE ATT&CK ids this rule names

Related rules

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/registry/registry_set/registry_set_ime_non_default_extension.yml

Sources and licences

  • SigmaHQ

    "Uncommon Extension In Keyboard Layout IME File Registry Value" by X__Junior (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/registry/registry_set/registry_set_ime_non_default_extension.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Uncommon Extension In Keyboard Layout IME File Registry Value",
entity page, dataset version ref-6a77b741c448, updated 2023-11-21T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/b888e3f2-224d-4435-b00b-9dd66e9ea1f1 (accessed 2026-11-03).
Underlying source: SigmaHQ rule b888e3f2-224d-4435-b00b-9dd66e9ea1f1, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.