---
id: CVE-2021-3909
aliases:
  - GHSA-8cvr-4rrf-f244
  - GO-2022-0250
title: Infinite open connection causes OctoRPKI to hang forever
summary: Infinite open connection causes OctoRPKI to hang forever
severity: medium
cvss: 4.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H'
vendor: cloudflare
product: github.com/cloudflare/cfrpki
ecosystem: go
affected:
  - github.com/cloudflare/cfrpki < 1.4.0
patched:
  - github.com/cloudflare/cfrpki 1.4.0
published: '2021-11-10'
updated: '2026-07-08'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-8cvr-4rrf-f244'
references:
  - url: >-
      https://github.com/cloudflare/cfrpki/security/advisories/GHSA-8cvr-4rrf-f244
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2021-3909'
  - url: 'https://github.com/cloudflare/cfrpki'
  - url: 'https://github.com/cloudflare/cfrpki/releases/tag/v1.4.0'
  - url: 'https://www.debian.org/security/2021/dsa-5033'
  - url: 'https://www.debian.org/security/2022/dsa-5041'
tags:
  - osv
  - go
epss: 0.01562
epssPercentile: 0.74187
ingestedAt: '2026-07-09T18:56:36.221Z'
---

## Overview

OctoRPKI (github.com/cloudflare/cfrpki/cmd/octorpki) does not limit the length of a connection, allowing for a slowloris DOS attack to take place which makes OctoRPKI wait forever. Specifically, the repository that OctoRPKI sends HTTP requests to will keep the connection open for a day before a response is returned, but does keep drip feeding new bytes to keep the connection alive.

## Patches

## For more information
If you have any questions or comments about this advisory email us at security@cloudflare.com


## Affected packages

- `github.com/cloudflare/cfrpki < 1.4.0`

## Remediation

Upgrade to a patched release:

- `github.com/cloudflare/cfrpki 1.4.0`