sigmahighHunting

CobaltStrike Load by Rundll32

Rundll32 can be use by Cobalt Strike with StartW function to load DLLs from the command line.

MITRE ATT&CK

defense-evasion

Detection Query

selection_rundll:
  - Image|endswith: \rundll32.exe
  - OriginalFileName: RUNDLL32.EXE
  - CommandLine|contains:
      - rundll32.exe
      - "rundll32 "
selection_params:
  CommandLine|contains: .dll
  CommandLine|endswith:
    - " StartW"
    - ",StartW"
condition: all of selection*

Author

Wojciech Lesicki

Created

2021-06-01

Data Sources

windowsProcess Creation Events

Platforms

windows

References

Tags

attack.defense-evasionattack.t1218.011

Raw Content

title: CobaltStrike Load by Rundll32
id: ae9c6a7c-9521-42a6-915e-5aaa8689d529
status: test
description: Rundll32 can be use by Cobalt Strike with StartW function to load DLLs from the command line.
references:
    - https://www.cobaltstrike.com/help-windows-executable
    - https://redcanary.com/threat-detection-report/
    - https://thedfirreport.com/2020/10/18/ryuk-in-5-hours/
author: Wojciech Lesicki
date: 2021-06-01
modified: 2022-09-16
tags:
    - attack.defense-evasion
    - attack.t1218.011
logsource:
    category: process_creation
    product: windows
detection:
    selection_rundll:
        - Image|endswith: '\rundll32.exe'
        - OriginalFileName: RUNDLL32.EXE
        - CommandLine|contains:
              - 'rundll32.exe'
              - 'rundll32 '
    selection_params:
        CommandLine|contains: '.dll'
        CommandLine|endswith:
            - ' StartW'
            - ',StartW'
    condition: all of selection*
falsepositives:
    - Unknown
level: high