Suspicious PsExec Execution — Sigma Rule

Rule metadata and linked tags

Author: Samir Bousseaden. Source status: test; severity: high. Source dates: 2019-04-03 / 2022-08-11.

{
  "product": "windows",
  "service": "security",
  "definition": "The advanced audit policy setting \"Object Access > Audit Detailed File Share\" must be configured for Success/Failure"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ae489024e3d788e6700bb91c63a233dc568224ea8708f335f9dce283f7d01228

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: Suspicious PsExec Execution
id: c462f537-a1e3-41a6-b5fc-b2c2cef9bf82
status: test
description: detects execution of psexec or paexec with renamed service name, this rule helps to filter out the noise if psexec is used for legit purposes or if attacker uses a different psexec client other than sysinternal one
references:
    - https://web.archive.org/web/20230329171218/https://blog.menasec.net/2019/02/threat-hunting-3-detecting-psexec.html
author: Samir Bousseaden
date: 2019-04-03
modified: 2022-08-11
tags:
    - attack.lateral-movement
    - attack.t1021.002
logsource:
    product: windows
    service: security
    definition: 'The advanced audit policy setting "Object Access > Audit Detailed File Share" must be configured for Success/Failure'
detection:
    selection1:
        EventID: 5145
        ShareName: '\\\\\*\\IPC$' # looking for the string \\*\IPC$
        RelativeTargetName|endswith:
            - '-stdin'
            - '-stdout'
            - '-stderr'
    filter:
        RelativeTargetName|startswith: 'PSEXESVC'
    condition: selection1 and not filter
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://web.archive.org/web/20230329171218/https://blog.menasec.net/2019/02/threat-hunting-3-detecting-psexec.html