Windows Process Creation: Suspicious ShellExec_RunDLL Command-Line Usage

Detects Windows command lines containing ShellExec_RunDLL along with other suspicious execution indicators.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-09-01
Updated
2026-07-30
title: "Windows Process Creation: Suspicious ShellExec_RunDLL Command-Line Usage"
id: fea07ae2-4e64-4bf5-a5cb-049eba8f3a65
related:
  - id: 36c5146c-d127-4f85-8e21-01bf62355d5a
    type: obsolete
  - id: 8823e85d-31d8-473e-b7f4-92da070f0fc6
    type: similar
  - id: d87bd452-6da1-456e-8155-7dc988157b7d
    type: derived
status: test
description: This rule flags Windows process creation events where the command line contains ShellExec_RunDLL, indicating an attempt to launch other commands indirectly through Windows shell execution. It also looks for additional suspicious command-line fragments consistent with commonly abused execution paths and tools. The detection relies on process creation telemetry and inspection of the CommandLine field to match these specific string patterns.
references:
  - https://redcanary.com/blog/raspberry-robin/
  - https://www.microsoft.com/en-us/security/blog/2022/10/27/raspberry-robin-worm-part-of-larger-ecosystem-facilitating-pre-ransomware-activity/
  - https://github.com/SigmaHQ/sigma/issues/1009
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_rundll32_susp_shellexec_execution.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2022-09-01
modified: 2022-12-30
tags:
  - attack.stealth
logsource:
  category: process_creation
  product: windows
detection:
  selection_openasrundll:
    CommandLine|contains: ShellExec_RunDLL
  selection_suspcli:
    CommandLine|contains:
      - \Desktop\
      - \Temp\
      - \Users\Public\
      - comspec
      - iex
      - Invoke-
      - msiexec
      - odbcconf
      - regsvr32
  condition: all of selection_*
falsepositives:
  - Unknown
level: high
license: DRL-1.1