Detection rules › Sigma
Elevated System Shell Spawned From Uncommon Parent Location
Detects when a shell program such as the Windows command prompt or PowerShell is launched with system privileges from a uncommon parent location.
Known false positives
- Some legitimate applications may spawn shells from uncommon parent locations. Apply additional filters and perform an initial baseline before deploying.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
Rule body
title: Elevated System Shell Spawned From Uncommon Parent Location
id: 178e615d-e666-498b-9630-9ed363038101
related:
- id: 61065c72-5d7d-44ef-bf41-6a36684b545f
type: similar
status: test
description: Detects when a shell program such as the Windows command prompt or PowerShell is launched with system privileges from a uncommon parent location.
references:
- https://github.com/Wh04m1001/SysmonEoP
author: frack113, Tim Shelton (update fp)
date: 2022-12-05
modified: 2025-03-06
tags:
- attack.privilege-escalation
- attack.execution
- attack.t1059
logsource:
product: windows
category: process_creation
detection:
selection_shell:
- Image|endswith:
- '\powershell.exe'
- '\powershell_ise.exe'
- '\pwsh.exe'
- '\cmd.exe'
- OriginalFileName:
- 'PowerShell.EXE'
- 'powershell_ise.EXE'
- 'pwsh.dll'
- 'Cmd.Exe'
selection_user:
User|contains: # covers many language settings
- 'AUTHORI'
- 'AUTORI'
LogonId: '0x3e7'
filter_main_generic:
# Example 1:
# C:\Program Files\erl-23.2\erts-11.1.4\bin\erl.exe" -service_event ErlSrv_RabbitMQ -nohup -sname rabbit@localhost -s rabbit boot -boot start_sasl +W w +MBas ageffcbf +MHas ageffcbf +MBlmbcs 512 +MHlmbcs 512 +MMmcs 30 +P 1048576 +t 5000000 +stbt db +zdbbl 128000 +sbwt none +sbwtdcpu none +sbwtdio none -kernel inet_dist_listen_min 25672 -kernel inet_dist_listen_max 25672 -lager crash_log false -lager handlers []
# Example 2:
# ParentImage: C:\Program Files (x86)\Varonis\DatAdvantage\GridCollector\VrnsRealTimeAlertsSvc.exe" /appid 000000ad-cb03-500b-9459-c46d000000ad
# CommandLine: C:\Windows\system32\cmd.exe /c C:\Program Files "(x86)\Varonis\DatAdvantage\GridCollector\handle_scopes.cmd C:\Collector" Working Share\VaronisWorkDirectoryCollector
ParentImage|contains:
- ':\Program Files (x86)\'
- ':\Program Files\'
- ':\ProgramData\'
- ':\Windows\System32\'
- ':\Windows\SysWOW64\'
- ':\Windows\Temp\' # Installers
- ':\Windows\WinSxS\'
filter_optional_manageengine:
# Example:
# ParentImage: C:/ManageEngine/ADManager Plus/pgsql/bin/postgres.exe" --forkarch 5380
# CommandLine: C:\Windows\system32\cmd.exe /c "IF EXIST archive.bat (archive.bat pg_wal\000000010000008E000000EA 000000010000008E000000EA)
ParentImage|endswith: ':\ManageEngine\ADManager Plus\pgsql\bin\postgres.exe'
Image|endswith: '\cmd.exe'
filter_optional_asgard:
CommandLine|contains: ':\WINDOWS\system32\cmd.exe /c "'
CurrentDirectory|contains: ':\WINDOWS\Temp\asgard2-agent\'
filter_optional_ibm_spectrumprotect:
ParentImage|contains: ':\IBM\SpectrumProtect\webserver\scripts\'
CommandLine|contains: ':\IBM\SpectrumProtect\webserver\scripts\'
filter_main_parent_null:
ParentImage: null
filter_main_parent_empty:
ParentImage:
- ''
- '-'
condition: all of selection_* and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
- Some legitimate applications may spawn shells from uncommon parent locations. Apply additional filters and perform an initial baseline before deploying.
level: medium
Stages and Predicates
Stage 0: condition
all of selection_* and not 1 of filter_main_* and not 1 of filter_optional_*Stage 1: selection_shell
selection_shell:
- Image|endswith:
- '\powershell.exe'
- '\powershell_ise.exe'
- '\pwsh.exe'
- '\cmd.exe'
- OriginalFileName:
- 'PowerShell.EXE'
- 'powershell_ise.EXE'
- 'pwsh.dll'
- 'Cmd.Exe'
Stage 2: selection_user
selection_user:
User|contains:
- 'AUTHORI'
- 'AUTORI'
LogonId: '0x3e7'
Stage 3: not filter_main_*
filter_main_generic:
ParentImage|contains:
- ':\Program Files (x86)\'
- ':\Program Files\'
- ':\ProgramData\'
- ':\Windows\System32\'
- ':\Windows\SysWOW64\'
- ':\Windows\Temp\'
- ':\Windows\WinSxS\'
filter_main_parent_null:
ParentImage: null
filter_main_parent_empty:
ParentImage:
- ''
- '-'
Stage 4: not filter_optional_*
filter_optional_manageengine:
ParentImage|endswith: ':\ManageEngine\ADManager Plus\pgsql\bin\postgres.exe'
Image|endswith: '\cmd.exe'
filter_optional_asgard:
CommandLine|contains: ':\WINDOWS\system32\cmd.exe /c "'
CurrentDirectory|contains: ':\WINDOWS\Temp\asgard2-agent\'
filter_optional_ibm_spectrumprotect:
ParentImage|contains: ':\IBM\SpectrumProtect\webserver\scripts\'
CommandLine|contains: ':\IBM\SpectrumProtect\webserver\scripts\'
Exclusions
The rule actively suppresses these predicates.
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Image | ends_with |
| field:"Image" kind:ends_with |
LogonId | eq |
| field:"LogonId" kind:eq value:"0x3e7" |
OriginalFileName | eq |
| field:"OriginalFileName" kind:eq |
User | match |
| field:"user" kind:match |