File Download From IP Based URL Via CertOC.EXE — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2023-10-18 / not supplied.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: cbe89a97c30152a6cc3013df3fb896506a7deda8766a761639d6f94c7062ffd1

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 From IP Based URL Via CertOC.EXE
id: b86f6dea-0b2f-41f5-bdcc-a057bd19cd6a
related:
    - id: 70ad0861-d1fe-491c-a45f-fa48148a300d
      type: similar
status: test
description: Detects when a user downloads a file from an IP based URL using CertOC.exe
references:
    - https://lolbas-project.github.io/lolbas/Binaries/Certoc/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-10-18
tags:
    - attack.command-and-control
    - attack.execution
    - attack.t1105
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\certoc.exe'
        - OriginalFileName: 'CertOC.exe'
    selection_ip:
        CommandLine|re: '://[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}'
    selection_cli:
        CommandLine|contains: '-GetCACAPS'
    condition: all of selection*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

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