CVE-2026-42592: Gotenberg DNS rebinding SSRF in Chromium URL conversion

CVE-2026-42592 · Severity: medium · CVSS 5.3 · Published 2026-05-14

Gotenberg is a tool used to convert web pages and documents into PDF files. A security flaw allows attackers to bypass safety filters and force the system to access internal company servers or private cloud data that should be off-limits. By tricking the system into connecting to these private addresses, an attacker can capture sensitive internal information and receive it back in the form of a generated PDF.

Technologies: github.com/gotenberg/gotenberg/v7 (Go), github.com/gotenberg/gotenberg/v8 (Go), Gotenberg. Vendors: Go, Gotenberg.

Quick answers

Is CVE-2026-42592 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-42592 being exploited in the wild.
How severe is CVE-2026-42592?
Medium severity, with a CVSS score of 5.3, published 14 May 2026.
Which products and versions are affected?
github.com/gotenberg/gotenberg/v7 (Go) SEMVER:introduced=0; github.com/gotenberg/gotenberg/v8 (Go) <= 8.31.0, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=8.31.0; Gotenberg < 8.32.0, <= 8.31.0.
Is there a fix for CVE-2026-42592?
A patch was published on 2026-05-14: Fix released in version 8.32.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-42592 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-42592?
Check whether you run github.com/gotenberg/gotenberg/v7 (Go), github.com/gotenberg/gotenberg/v8 (Go) or Gotenberg at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A Time-of-Check Time-of-Use (TOCTOU) vulnerability exists in Gotenberg's Chromium-based URL conversion. The 'FilterOutboundURL' function validates a hostname against a private-address deny-list but discards the resolved IP address. Chromium then performs its own independent DNS resolution when navigating. An attacker controlling a DNS server with a short TTL can provide a public IP during the initial validation and a private/internal IP (such as 127.0.0.1 or 169.254.169.254) during Chromium's actual connection phase. This DNS rebinding attack allows unauthenticated remote attackers to perform Server-Side Request Forgery (SSRF) and exfiltrate internal service responses via the rendered PDF output. The issue is fixed in version 8.32.0 by ensuring resolved IPs are pinned.

Affected products

  • Gotenberg Gotenberg < 8.32.0

Identifiers

  • CVE-2026-42592
  • GHSA-2pmr-289p-44r3
  • GO-2026-4990

Timeline

  • 2026-04-30: advisory: GitHub security advisory published by maintainers
  • 2026-05-14: disclosed: CVE published to NVD
  • 2026-05-14: patched: Fix released in version 8.32.0

References

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