Privilege SeMachineAccountPrivilege abuse

title: Privilege SeMachineAccountPrivilege abuse
description: Detects scenarios where an attacker abuse the SeMachineAccountPrivilege which allows per default any authenticated user to join a computer to the domain. Later on, this computer account can be manipulated in order to elevate privileges.
requirements: despite of this event marked as a "sensitive privilege", I was only able to trigger it by having the audit for "non sensitive privileges" activated.
correlation: correlate with ID 4741 (computer created) using field SubjectLogonId. See rule "Computer account created with privileges" for advance correlation.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0004-Privilege%20Escalation/T1068-Exploitation%20for%20Privilege%20Escalation
- https://exploit.ph/cve-2021-42287-cve-2021-42278-weaponisation.html
- https://www.thehacker.recipes/ad/movement/kerberos/samaccountname-spoofing
- https://support.microsoft.com/en-us/topic/kb5008380-authentication-updates-cve-2021-42287-9dafac11-e0d0-4cb8-959a-143bd0201041
- https://github.com/WazeHell/sam-the-admin
- https://github.com/cube0x0/noPac
- https://github.com/ly4k/Pachine
- https://cloudbrothers.info/en/exploit-kerberos-samaccountname-spoofing/
tags:
- attack.privilege_escalation
- attack.t1068
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4673
    PrivilegeList: SeMachineAccountPrivilege
    #ProcessName|endswith: \Windows\System32\lsass.exe
  filter:
    - SubjectUserSid: "S-1-5-18"
    - SubjectUserName: '%admin_acounts%'
  condition: selection and not filter
falsepositives:
- Users (shouldn't) or administrators joining a computer to the domain, server provisionning software
level: medium