CVE-2026-42593: Gotenberg Arbitrary PDF Read via Path Traversal in Conversion Routes

CVE-2026-42593 · Severity: medium · CVSS 5.3 · Published 2026-05-14

Gotenberg is a tool used to convert various file formats into PDF documents. A security flaw allows unauthorized users to read sensitive PDF files stored on the server or within the application's environment. By sending a specially crafted request, an attacker can force the system to include local files as 'stamps' or 'watermarks' in a generated PDF, which is then returned to the attacker.

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

Quick answers

Is CVE-2026-42593 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-42593 being exploited in the wild.
How severe is CVE-2026-42593?
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-2026-42593?
A patch was published on 2026-05-14: Vulnerability fixed in version 8.32.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-42593 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-42593?
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 path traversal and external control of filename vulnerability exists in Gotenberg's merge, split, and conversion routes (LibreOffice and Chromium). The application fails to validate the 'stampExpression' and 'watermarkExpression' parameters when 'stampSource' or 'watermarkSource' is set to 'pdf' but no file is actually uploaded. In these cases, the application uses the user-provided file path directly. The underlying 'pdfcpu' engine then opens the file at that path and composites it onto the output PDF returned to the user. This allows an attacker to read any PDF file accessible to the Gotenberg process and can also be used as a file-existence oracle for non-PDF files. The issue is fixed in version 8.32.0.

Affected products

  • Gotenberg Gotenberg < 8.32.0

Identifiers

  • CVE-2026-42593
  • GHSA-3cv5-q585-h563
  • GO-2026-5080

Timeline

  • 2026-04-30: advisory: GitHub Security Advisory published
  • 2026-05-14: disclosed: CVE published to NVD
  • 2026-05-14: patched: Vulnerability fixed in version 8.32.0

References

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