Detection rules › Sigma
Suspicious Child Process Created as System
Detection of child processes spawned with SYSTEM privileges by parents with LOCAL SERVICE or NETWORK SERVICE accounts
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Privilege Escalation | T1134.002 Access Token Manipulation: Create Process with Token |
| Stealth | T1134.002 Access Token Manipulation: Create Process with Token |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
Rule body yaml
title: Suspicious Child Process Created as System
id: 590a5f4c-6c8c-4f10-8307-89afe9453a9d
status: test
description: Detection of child processes spawned with SYSTEM privileges by parents with LOCAL SERVICE or NETWORK SERVICE accounts
references:
- https://speakerdeck.com/heirhabarov/hunting-for-privilege-escalation-in-windows-environment
- https://foxglovesecurity.com/2016/09/26/rotten-potato-privilege-escalation-from-service-accounts-to-system/
- https://github.com/antonioCoco/RogueWinRM
- https://twitter.com/Cyb3rWard0g/status/1453123054243024897
author: Teymur Kheirkhabarov, Roberto Rodriguez (@Cyb3rWard0g), Open Threat Research (OTR)
date: 2019-10-26
modified: 2024-12-01
tags:
- attack.privilege-escalation
- attack.stealth
- attack.t1134.002
logsource:
category: process_creation
product: windows
definition: 'Requirements: ParentUser field needs sysmon >= 13.30'
detection:
selection:
ParentUser|contains:
- 'AUTHORI'
- 'AUTORI'
ParentUser|endswith:
- '\NETWORK SERVICE'
- '\LOCAL SERVICE'
User|contains: # covers many language settings
- 'AUTHORI'
- 'AUTORI'
User|endswith: # System
- '\SYSTEM'
- '\Système'
- '\СИСТЕМА'
IntegrityLevel:
- 'System'
- 'S-1-16-16384'
filter_rundll32:
Image|endswith: '\rundll32.exe'
CommandLine|contains: 'DavSetCookie'
condition: selection and not 1 of filter_*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_*Stage 1: selection
selection:
ParentUser|contains:
- 'AUTHORI'
- 'AUTORI'
ParentUser|endswith:
- '\NETWORK SERVICE'
- '\LOCAL SERVICE'
User|contains:
- 'AUTHORI'
- 'AUTORI'
User|endswith:
- '\SYSTEM'
- '\Système'
- '\СИСТЕМА'
IntegrityLevel:
- 'System'
- 'S-1-16-16384'
Stage 2: not filter_rundll32
filter_rundll32:
Image|endswith: '\rundll32.exe'
CommandLine|contains: 'DavSetCookie'
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
CommandLine | match | DavSetCookie |
Image | ends_with | \rundll32.exe |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
IntegrityLevel | eq |
|
ParentUser | ends_with |
|
ParentUser | match |
|
User | ends_with |
|
User | match |
|