Certificate Exported Via Certutil.EXE — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems), Jonhnathan Ribeiro, oscd.community, Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2023-02-15 / 2024-03-05.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: fa49b82cd59f495bc0e695ec755d943dd84efa403be667865134bd9f566e37e5

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Certificate Exported Via Certutil.EXE
id: 3ffd6f51-e6c1-47b7-94b4-c1e61d4117c5
status: test
description: Detects the execution of the certutil with the "exportPFX" flag which allows the utility to export certificates.
references:
    - https://www.splunk.com/en_us/blog/security/a-golden-saml-journey-solarwinds-continued.html
author: Florian Roth (Nextron Systems), Jonhnathan Ribeiro, oscd.community, Nasreddine Bencherchali (Nextron Systems)
date: 2023-02-15
modified: 2024-03-05
tags:
    - attack.stealth
    - attack.t1027
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\certutil.exe'
        - OriginalFileName: 'CertUtil.exe'
    selection_cli:
        CommandLine|contains|windash: '-exportPFX '
    condition: all of selection_*
falsepositives:
    - There legitimate reasons to export certificates. Investigate the activity to determine if it's benign
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_certutil_export_pfx/info.yml

Original YAML and metadata in JSON

False positives

• There legitimate reasons to export certificates. Investigate the activity to determine if it's benign

Source references

• https://www.splunk.com/en_us/blog/security/a-golden-saml-journey-solarwinds-continued.html