HackTool - Koh Default Named Pipe — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: critical. Source dates: 2022-07-08 / 2023-08-07.

{
  "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. How to test detection? 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: 3090dbb25266e9bea297fc3b65c48ed6834e6354ca4bfb24e2d2cc0af94a45a8

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: HackTool - Koh Default Named Pipe
id: 0adc67e0-a68f-4ffd-9c43-28905aad5d6a
status: test
description: Detects creation of default named pipes used by the Koh tool
references:
    - https://github.com/GhostPack/Koh/blob/0283d9f3f91cf74732ad377821986cfcb088e20a/Clients/BOF/KohClient.c#L12
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-07-08
modified: 2023-08-07
tags:
    - attack.privilege-escalation
    - attack.credential-access
    - attack.stealth
    - attack.t1528
    - attack.t1134.001
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. How to test detection? 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:
        PipeName|contains:
            - '\imposecost'
            - '\imposingcost'
    condition: selection
falsepositives:
    - Unlikely
level: critical

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://github.com/GhostPack/Koh/blob/0283d9f3f91cf74732ad377821986cfcb088e20a/Clients/BOF/KohClient.c#L12