File Download via CertOC.EXE — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: medium. Source dates: 2022-05-16 / 2023-10-18.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 90e8c995e4d21c2098a46e62036673f54f844ba707ae93d0fedfa5755056d3f1

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: File Download via CertOC.EXE
id: 70ad0861-d1fe-491c-a45f-fa48148a300d
related:
    - id: b86f6dea-0b2f-41f5-bdcc-a057bd19cd6a
      type: similar
status: test
description: Detects when a user downloads a file by using CertOC.exe
references:
    - https://lolbas-project.github.io/lolbas/Binaries/Certoc/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-05-16
modified: 2023-10-18
tags:
    - attack.command-and-control
    - attack.t1105
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\certoc.exe'
        - OriginalFileName: 'CertOC.exe'
    selection_cli:
        CommandLine|contains|all:
            - '-GetCACAPS'
            - 'http'
    condition: all of selection*
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://lolbas-project.github.io/lolbas/Binaries/Certoc/