Windows rundll32.exe Command-Line RunDLL or Control_RunDLL Execution

Alerts on rundll32.exe process launches whose command lines end with RunDLL/Control_RunDLL, indicative of DLL function loading.

FreeReviewedSigma · Critical · v5
Product
windows
Category
process_creation
Author
FPT.EagleEye (SigmaHQ), DRL 1.1
Published
2020-12-25
Updated
2026-07-31
title: Windows rundll32.exe Command-Line RunDLL or Control_RunDLL Execution
id: b031c283-0667-468e-8373-a0a07ddad04e
status: test
description: This rule flags Windows process creation events where rundll32.exe is executed with a command line ending in ,RunDLL or ,Control_RunDLL. Such patterns are commonly used to load exported functions from DLLs via rundll32, which can be leveraged to execute malicious code with reduced direct payload visibility. The detection relies on process creation telemetry including Image/OriginalFileName and the full CommandLine, and it excludes likely benign Control_RunDLL patterns involving .dll immediately before the argument and a specific parent process (tracker.exe).
references:
  - https://paste.cryptolaemus.com/emotet/2020/12/22/emotet-malware-IoCs_12-22-20.html
  - https://cyber.wtf/2021/11/15/guess-whos-back/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2020/Malware/Emotet/proc_creation_win_malware_emotet_rundll32_execution.yml
author: FPT.EagleEye, Huntrule Team
date: 2020-12-25
modified: 2023-02-21
tags:
  - attack.stealth
  - attack.t1218.011
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    - Image|endswith: \rundll32.exe
    - OriginalFileName: RUNDLL32.EXE
  selection_cli:
    CommandLine|endswith:
      - ",RunDLL"
      - ",Control_RunDLL"
  filter_legitimate_dll:
    CommandLine|endswith:
      - .dll,Control_RunDLL
      - .dll",Control_RunDLL
      - .dll',Control_RunDLL
  filter_ide:
    ParentImage|endswith: \tracker.exe
  condition: all of selection_* and not 1 of filter_*
falsepositives:
  - Unknown
level: critical
license: DRL-1.1
related:
  - id: 54e57ce3-0672-46eb-a402-2c0948d5e3e9
    type: derived