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

title: Suspicious New Root Certificate Installed Through CertMgr.EXE (via process_creation)
id: 723305af-2b35-54bc-b195-7b6d6fa67b3f
status: stable
description: This rule detects execution of "certmgr" with the "add" 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
    - https://securelist.com/to-crypt-or-to-mine-that-is-the-question/86307/
author: Huntrule Team
date: 2026-05-28
tags:
    - attack.defense-impairment
    - attack.t1553.004
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\CertMgr.exe'
        - OriginalFileName: 'CERTMGT.EXE'
    selection_cli:
        CommandLine|contains|all:
            - '/add'
            - 'root'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium