CobaltStrike Named Pipe Patterns — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems), Christian Burkard (Nextron Systems). Source status: test; severity: high. Source dates: 2021-07-30 / 2024-01-26.

{
  "product": "windows",
  "category": "pipe_created",
  "definition": "Note that you have to configure logging for Named Pipe Events in Sysmon config (Event ID 17 and Event ID 18). The basic configuration is in popular sysmon configuration (https://github.com/SwiftOnSecurity/sysmon-config), but it is worth verifying. You can also use other repo, e.g. https://github.com/Neo23x0/sysmon-config, https://github.com/olafhartong/sysmon-modular You can also use other repo, e.g. https://github.com/Neo23x0/sysmon-config, https://github.com/olafhartong/sysmon-modular. How to test detection? You can always use Cobalt Strike, but also you can check powershell script from this site https://svch0st.medium.com/guide-to-named-pipes-and-hunting-for-cobalt-strike-pipes-dc46b2c5f575"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: df71e2e571dc55ce3648db73da3a708948db011538ec39320fcde5e14503f6b3

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: CobaltStrike Named Pipe Patterns
id: 85adeb13-4fc9-4e68-8a4a-c7cb2c336eb7
related:
    - id: 0e7163d4-9e19-4fa7-9be6-000c61aad77a # Regex
      type: similar
    - id: d5601f8c-b26f-4ab0-9035-69e11a8d4ad2 # Generic
      type: similar
status: test
description: Detects the creation of a named pipe with a pattern found in CobaltStrike malleable C2 profiles
references:
    - https://svch0st.medium.com/guide-to-named-pipes-and-hunting-for-cobalt-strike-pipes-dc46b2c5f575
    - https://gist.github.com/MHaggis/6c600e524045a6d49c35291a21e10752
author: Florian Roth (Nextron Systems), Christian Burkard (Nextron Systems)
date: 2021-07-30
modified: 2024-01-26
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1055
    - stp.1k
logsource:
    product: windows
    category: pipe_created
    definition: 'Note that you have to configure logging for Named Pipe Events in Sysmon config (Event ID 17 and Event ID 18). The basic configuration is in popular sysmon configuration (https://github.com/SwiftOnSecurity/sysmon-config), but it is worth verifying. You can also use other repo, e.g. https://github.com/Neo23x0/sysmon-config, https://github.com/olafhartong/sysmon-modular You can also use other repo, e.g. https://github.com/Neo23x0/sysmon-config, https://github.com/olafhartong/sysmon-modular. How to test detection? You can always use Cobalt Strike, but also you can check powershell script from this site https://svch0st.medium.com/guide-to-named-pipes-and-hunting-for-cobalt-strike-pipes-dc46b2c5f575'
detection:
    selection_malleable_profile_generic:
        - PipeName|startswith:
              - '\DserNamePipe'
              - '\f4c3'
              - '\f53f'
              - '\fullduplex_'
              - '\mojo.5688.8052.183894939787088877'
              - '\mojo.5688.8052.35780273329370473'
              - '\MsFteWds'
              - '\msrpc_'
              - '\mypipe-f'
              - '\mypipe-h'
              - '\ntsvcs'
              - '\PGMessagePipe'
              - '\rpc_'
              - '\scerpc'
              - '\SearchTextHarvester'
              - '\spoolss'
              - '\win_svc'
              - '\win\msrpc_'
              - '\windows.update.manager'
              - '\wkssvc'
        - PipeName:
              - '\demoagent_11'
              - '\demoagent_22'
    selection_malleable_profile_catalog_change_listener:
        PipeName|startswith: '\Winsock2\CatalogChangeListener-'
        PipeName|endswith: '-0,'
    filter_main_generic:
        PipeName:
            - '\wkssvc'
            - '\spoolss'
            - '\scerpc'
            - '\ntsvcs'
            - '\SearchTextHarvester'
            - '\PGMessagePipe'
            - '\MsFteWds'
    filter_optional_websense:
        Image|contains:
            - ':\Program Files\Websense\'
            - ':\Program Files (x86)\Websense\'
        PipeName|startswith:
            - '\DserNamePipeR'
            - '\DserNamePipeW'
    condition: 1 of selection_malleable_profile_* and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Chrome instances using the exact same pipe name "mojo.xxx"
    - Websense Endpoint using the pipe name "DserNamePipe(R|W)\d{1,5}"
    - Some applications may just coincidentally use the pipe names which contain the same prefix as the ones used by CobaltStrike, e.g. "f4c3"
level: high

Original YAML and metadata in JSON

False positives

• Chrome instances using the exact same pipe name "mojo.xxx"
• Websense Endpoint using the pipe name "DserNamePipe(R|W)\d{1,5}"
• Some applications may just coincidentally use the pipe names which contain the same prefix as the ones used by CobaltStrike, e.g. "f4c3"

Source references

• https://svch0st.medium.com/guide-to-named-pipes-and-hunting-for-cobalt-strike-pipes-dc46b2c5f575
• https://gist.github.com/MHaggis/6c600e524045a6d49c35291a21e10752