---
id: "CVE-2026-126799"
page: "https://infrastack.ai/live/CVE-2026-126799"
kind: "vulnerability"
aliases: ["CVE-2026-126799"]
title: "Gotenberg: IPv6 zone identifiers bypass private-IP checks, enabling server-side request forgery"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["docker", "gotenberg", "package", "self-hosted"]
not_affected_if: ["no-user-supplied-urls", "version-8.38.0-or-later"]
published_at: "2026-11-11T21:16:43+00:00"
first_seen_at: "2026-11-11T21:29:07+00:00"
updated_at: "2026-11-11T21:30:45+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126799", "first_seen_at": "2026-11-11T21:29:07+00:00"}]
exploit_sources: []
---

# Gotenberg: IPv6 zone identifiers bypass private-IP checks, enabling server-side request forgery

Link for people: https://infrastack.ai/live/CVE-2026-126799 (this .md is for agents)

Gotenberg's private-IP deny list can be bypassed by appending an IPv6 zone identifier such as %25eth0 to a blocked address. An unauthenticated attacker can make the server fetch internal services and read the responses inside the returned PDF.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the running Gotenberg version (for example with `gotenberg --version` or the container image tag); versions `8.31.0` through `8.37.x` are in the affected range.
- Look for Gotenberg exposed to untrusted users with `downloadFrom`, webhook, or Chromium/LibreOffice URL inputs enabled.

## Fix

- Gotenberg: upgrade to `8.38.0` or later.

## Timeline

- 2026-11-11T21:29:07+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126799

## Documents

- [advisory] Vendor advisory: github.com https://github.com/gotenberg/gotenberg/security/advisories/GHSA-fqg9-x2xw-5crx
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/gotenberg-8.31.0-before-8.38.0-ssrf-via-ipv6-zone-identifiers-in-ispublicip
- [fix] Patch: github.com https://github.com/gotenberg/gotenberg/commit/8e850b1c932452627fba397f2005dd6fd57b9617
- [fix] Release notes: github.com https://github.com/gotenberg/gotenberg/releases/tag/v8.38.0

## From the sources

Gotenberg 8.31.0 before 8.38.0 contains a server-side request forgery vulnerability in IsPublicIP() that allows unauthenticated attackers to bypass private-IP deny-list protections using IPv6 zone identifiers. Attackers can append a zone such as %25eth0 to the unspecified address or blocked IPv6 prefixes in downloadFrom, webhook, or Chromium/LibreOffice URLs to reach internal services and read responses in the returned PDF.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_