CVE-2026-42595: Gotenberg: Server-Side Request Forgery via Chromium URL Endpoint with Redirect-Based Deny-List Bypass

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-05-14 · updated 2026-06-17
Weakness: CWE-918

Description

Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.32.0, Gotenberg's Chromium URL-to-PDF endpoint (/forms/chromium/convert/url) has no default protection against HTTP/HTTPS-based SSRF. The default deny-list regex only blocks file:// URIs. An unauthenticated attacker can point Chromium at any internal IP — including loopback, RFC 1918 ranges, and cloud metadata endpoints — and receive the response rendered as a PDF. Additionally, even when operators configure a custom deny-list, the protection is bypassed via HTTP redirects. Gotenberg's Chromium instance follows 302 redirects from an attacker-controlled external URL to internal targets without re-validating the redirect destination against the deny-list. This vulnerability is fixed in 8.32.0.

Affected products

gotenberg: before 8.32.0 — fixed in 8.32.0

How to fix

Upgrade to a fixed version: gotenberg 8.32.0. Check the vendor advisory for mitigations.

References

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