Suspicious New Root Certificate Installed Through Certutil.EXE (via process_creation)

title: Suspicious New Root Certificate Installed Through Certutil.EXE (via process_creation)
id: b39a364a-238d-5a1c-88a4-a9f00b0883c6
status: stable
description: This rule detects execution of "certutil" with the "addstore" flag to install a new certificate on the system. Adversaries may install a root certificate on a compromised system to avoid warnings when connecting to adversary controlled web servers.
references:
    - https://attack.mitre.org/techniques/T1553/004/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1553.004/T1553.004.md
author: Huntrule Team
date: 2026-02-19
tags:
    - attack.defense-impairment
    - attack.t1553.004
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\certutil.exe'
        - OriginalFileName: 'CertUtil.exe'
    selection_cli_add:
        CommandLine|contains|windash: '-addstore'
    selection_cli_store:
        CommandLine|contains: 'root'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_certutil_certificate_installation/info.yml