Sigma rule: Windows Processes Suspicious Parent Directory

Rule

Title

Windows Processes Suspicious Parent Directory

Status

test

Level

low

Author

vburov

Date

2019-02-23

Modified

2025-03-06

File

rules/windows/process_creation/proc_creation_win_susp_proc_wrong_parent.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detect suspicious parent processes of well-known Windows processes

Log source

product

windows

category

process_creation

Detection

selection:
    Image|endswith:
        - '\svchost.exe'
        - '\taskhost.exe'
        - '\lsm.exe'
        - '\lsass.exe'
        - '\services.exe'
        - '\lsaiso.exe'
        - '\csrss.exe'
        - '\wininit.exe'
        - '\winlogon.exe'
filter_sys:
    - ParentImage|endswith:
          - '\SavService.exe'
          - '\ngen.exe'
    - ParentImage|contains:
          - '\System32\'
          - '\SysWOW64\'
filter_msmpeng:
    ParentImage|contains:
        - '\Windows Defender\'
        - '\Microsoft Security Client\'
    ParentImage|endswith: '\MsMpEng.exe'
filter_null:
    - ParentImage: null
    - ParentImage:
          - ''
          - '-'
condition: selection and not 1 of filter_*

False positives (as the rule lists them)

• Some security products seem to spawn these

Tags

• attack.stealth
• attack.t1036.003
• attack.t1036.005

MITRE ATT&CK ids this rule names

• T1036.003
• T1036.005

References

• https://web.archive.org/web/20180718061628/https://securitybytes.io/blue-team-fundamentals-part-two-windows-processes-759fe15965e2
• https://www.carbonblack.com/2014/06/10/screenshot-demo-hunt-evil-faster-than-ever-with-carbon-black/
• https://www.13cubed.com/downloads/windows_process_genealogy_v2.pdf

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_susp_proc_wrong_parent.yml