Rundll32 Suspicious Command Line (Windows Event Log)

id: '27224.49649'
title: Rundll32 Suspicious Command Line
description: Threat actors using Gamarue, also referred to as Andromeda or Wauchos,
  have been observed abusing rundll32.exe using unusual strings for DLL names. This
  use case detects rundll32 executions with strings matching unusual patterns. Living
  Off the Land Binary and Scripts (LOLBAS) (LOLBIN)
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
  "<EventID>4688<" OR Type=Process) TERM(rundll32) OR "rundll32" | regex process="\x5c\x5c?[-_]{2,}[-_]{2,}[-_]{2,}.+,"|
  table _time, host, user, process, process_*, parent_process_* | bin span=1s | stats
  values(*) as * by _time, host '
techniques:
- defense-evasion:system binary proxy execution:rundll32
technique_id:
- T1218.011
data_category:
- Process command-line parameters
- Windows event logs
references:
- https://redcanary.com/threat-detection-report/threats/gamarue/
- https://redcanary.com/blog/lolbins-abuse/