Windows: File Download via CertOC.exe Using -GetCACAPS HTTP

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

Identifies process executions of CertOC.exe where the command line includes -GetCACAPS and an HTTP URL, indicating an attempt to download file content. This matters because CertOC.exe can be abused to retrieve remote resources, which may support further malicious activity. The detection relies on Windows process creation telemetry, matching the executable name/path and key substrings in the command line.

Reporting behind it

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Windows: File Download via CertOC.exe Using -GetCACAPS HTTP

Pivot detection · T1105 · 9 related

Changelog

v2

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

certoc-exe-file-download-via-getcacaps-http-on-windows-70ad0861

title: "Windows: File Download via CertOC.exe Using -GetCACAPS HTTP"
id: d7704bec-f020-4ccc-b50b-42468760cca4
related:
  - id: b86f6dea-0b2f-41f5-bdcc-a057bd19cd6a
    type: similar
  - id: 70ad0861-d1fe-491c-a45f-fa48148a300d
    type: derived
status: test
description: Identifies process executions of CertOC.exe where the command line includes -GetCACAPS and an HTTP URL, indicating an attempt to download file content. This matters because CertOC.exe can be abused to retrieve remote resources, which may support further malicious activity. The detection relies on Windows process creation telemetry, matching the executable name/path and key substrings in the command line.
references:
  - https://lolbas-project.github.io/lolbas/Binaries/Certoc/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_certoc_download.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
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
license: DRL-1.1

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