Windows: Child Process Spawned with SYSTEM Integrity by LOCAL/NETWORK SERVICE Parent
Alert on Windows executions where a SYSTEM-integrity child is spawned by a LOCAL SERVICE or NETWORK SERVICE parent, excluding a specific rundll32 pattern.
- Product
- windows
- Category
- process_creation
- Author
- Teymur Kheirkhabarov, Roberto Rodriguez (@Cyb3rWard0g), Open Threat Research (OTR) (SigmaHQ), DRL 1.1
- Published
- 2019-10-26
- Updated
- 2026-07-30
ATT&CK techniques
Priv Esc → Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags Windows process creation events where a child process runs with SYSTEM integrity while the parent process is associated with LOCAL SERVICE or NETWORK SERVICE accounts. Such behavior can indicate attempts to escalate privileges by leveraging service-context processes to spawn or execute SYSTEM-level code. The detection relies on process creation telemetry including parent user and child user/ integrity level fields, and it excludes cases involving rundll32.exe with a DavSetCookie command-line fragment.
Reporting behind it
- speakerdeck.comhttps://speakerdeck.com/heirhabarov/hunting-for-privilege-escalation-in-windows-environment
- foxglovesecurity.comhttps://foxglovesecurity.com/2016/09/26/rotten-potato-privilege-escalation-from-service-accounts-to-system/
- github.comhttps://github.com/antonioCoco/RogueWinRM
- twitter.comhttps://twitter.com/Cyb3rWard0g/status/1453123054243024897
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_susp_child_process_as_system_.yml
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Windows: Child Process Spawned with SYSTEM Integrity by LOCAL/NETWORK SERVICE Parent"
id: 52e53518-c385-41f8-9373-09877f096a6d
status: test
description: This rule flags Windows process creation events where a child process runs with SYSTEM integrity while the parent process is associated with LOCAL SERVICE or NETWORK SERVICE accounts. Such behavior can indicate attempts to escalate privileges by leveraging service-context processes to spawn or execute SYSTEM-level code. The detection relies on process creation telemetry including parent user and child user/ integrity level fields, and it excludes cases involving rundll32.exe with a DavSetCookie command-line fragment.
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
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_susp_child_process_as_system_.yml
author: Teymur Kheirkhabarov, Roberto Rodriguez (@Cyb3rWard0g), Open Threat Research (OTR), Huntrule Team
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:
- AUTHORI
- AUTORI
User|endswith:
- \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
license: DRL-1.1
related:
- id: 590a5f4c-6c8c-4f10-8307-89afe9453a9d
type: derived