Parent Process PID Spoofing

Identifies parent process spoofing used to thwart detection. Adversaries may spoof the parent process identifier (PPID) of a new process to evade process-monitoring defenses or to elevate privileges.

Rule type: eql

Rule indices:

logs-endpoint.events.*

Severity: high

Risk score: 73

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

https://blog.didierstevens.com/2017/03/20/

Tags:

Elastic
Host
Windows
Threat Detection
Defense Evasion

Version: 1

Added (Elastic Stack release): 7.14.0

Rule authors: Elastic

Rule license: Elastic License v2

Rule query

edit

/* This rule is compatible with Elastic Endpoint only */ sequence by
host.id, user.id with maxspan=5m [process where event.type == "start"
and process.Ext.token.integrity_level_name != "system" and (
process.pe.original_file_name : ("winword.exe", "excel.exe",
"outlook.exe", "powerpnt.exe", "eqnedt32.exe",
"fltldr.exe", "mspub.exe", "msaccess.exe", "powershell.exe",
"pwsh.exe", "cscript.exe",
"wscript.exe", "rundll32.exe", "regsvr32.exe", "msbuild.exe",
"mshta.exe", "wmic.exe", "cmstp.exe", "msxsl.exe") or
process.executable : ("?:\\Users\\*.exe",
"?:\\ProgramData\\*.exe",
"?:\\Windows\\Microsoft.NET\\*.exe",
"?:\\Windows\\Temp\\*.exe",
"?:\\Windows\\Tasks\\*") or process.code_signature.trusted != true
) ] by process.pid [process where event.type == "start" and
process.parent.Ext.real.pid > 0 and /* process.parent.Ext.real.pid
is only populated if the parent process pid doesn't match */ not
(process.name : "msedge.exe" and process.parent.name : "sihost.exe")
] by process.parent.Ext.real.pid

Threat mapping

edit

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Access Token Manipulation
- ID: T1134
- Reference URL: https://attack.mitre.org/techniques/T1134/

« Outbound Scheduled Task Activity via PowerShell Peripheral Device Discovery »