PUA - PAExec Default Named Pipe — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2022-10-26 / not supplied.

{
  "category": "pipe_created",
  "product": "windows",
  "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: 8cfb983dcd4832d29428b2273b0f6a207c76b63de84793cba07823dfa9cc6b00

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: PUA - PAExec Default Named Pipe
id: f6451de4-df0a-41fa-8d72-b39f54a08db5
status: test
description: Detects PAExec default named pipe
references:
    - https://github.com/microsoft/Microsoft-365-Defender-Hunting-Queries/blob/efa17a600b43c897b4b7463cc8541daa1987eeb4/Command%20and%20Control/C2-NamedPipe.md
    - https://github.com/poweradminllc/PAExec
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-26
tags:
    - attack.execution
    - attack.t1569.002
logsource:
    category: pipe_created
    product: windows
    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|startswith: '\PAExec'
    condition: selection
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/microsoft/Microsoft-365-Defender-Hunting-Queries/blob/efa17a600b43c897b4b7463cc8541daa1987eeb4/Command%20and%20Control/C2-NamedPipe.md
• https://github.com/poweradminllc/PAExec