Sigma rule: Potential Mpclient.DLL Sideloading Via OfflineScannerShell.EXE Execution

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-3ecb7af0901a, updated 2023-08-03T00:00:00.000Z.

Rule

Title
Potential Mpclient.DLL Sideloading Via OfflineScannerShell.EXE Execution
Status
test
Level
medium
Author
frack113
Date
2022-03-06
Modified
2023-08-03
File
rules/windows/process_creation/proc_creation_win_offlinescannershell_mpclient_sideloading.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of Windows Defender "OfflineScannerShell.exe" from its non standard directory.
The "OfflineScannerShell.exe" binary is vulnerable to DLL side loading and will load any DLL named "mpclient.dll" from the current working directory.

Log source

product
windows
category
process_creation

Detection

selection:
    - Image|endswith: '\OfflineScannerShell.exe'
    - OriginalFileName: 'OfflineScannerShell.exe'
filter_main_legit_dir:
    CurrentDirectory: 'C:\Program Files\Windows Defender\Offline\'
filter_main_empty:
    CurrentDirectory: ''
filter_main_null:
    CurrentDirectory: null
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.stealth
  • attack.t1218

MITRE ATT&CK ids this rule names

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/process_creation/proc_creation_win_offlinescannershell_mpclient_sideloading.yml

Sources and licences

  • SigmaHQ

    "Potential Mpclient.DLL Sideloading Via OfflineScannerShell.EXE Execution" by frack113 (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_offlinescannershell_mpclient_sideloading.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: Potential Mpclient.DLL Sideloading Via OfflineScannerShell.EXE Execution",
entity page, dataset version ref-3ecb7af0901a, updated 2023-08-03T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/02b18447-ea83-4b1b-8805-714a8a34546a (accessed 2026-11-03).
Underlying source: SigmaHQ rule 02b18447-ea83-4b1b-8805-714a8a34546a, 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.