Windows CertOC.exe Downloads File From IP-Based URL Using -GetCACAPS

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

This rule identifies process executions of CertOC.exe where the command line includes an IP-based URL and the -GetCACAPS parameter, consistent with downloading content from a remote host. Attackers can use LOLBin-style utilities to retrieve payloads while blending into normal Windows binary usage. Telemetry required is Windows process creation data, including Image/OriginalFileName and the full CommandLine string.

Reporting behind it

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Windows CertOC.exe Downloads File From IP-Based URL Using -GetCACAPS

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.

windows-certoc-exe-download-via-ip-based-url-getcacaps-b86f6dea

title: Windows CertOC.exe Downloads File From IP-Based URL Using -GetCACAPS
id: a41c5cff-860f-4d3e-802f-94afda4e08b9
related:
  - id: 70ad0861-d1fe-491c-a45f-fa48148a300d
    type: similar
  - id: b86f6dea-0b2f-41f5-bdcc-a057bd19cd6a
    type: derived
status: test
description: This rule identifies process executions of CertOC.exe where the command line includes an IP-based URL and the -GetCACAPS parameter, consistent with downloading content from a remote host. Attackers can use LOLBin-style utilities to retrieve payloads while blending into normal Windows binary usage. Telemetry required is Windows process creation data, including Image/OriginalFileName and the full CommandLine string.
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_direct_ip.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
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
license: DRL-1.1

Convert

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