Vulnerability · Published May 14, 2026 · Assigned by GitHub_M
CVE-2026-42589Gotenberg: Unauthenticated RCE via ExifTool Metadata Key Injection
Critical 9.8
In plain English
A critical-severity OS command injection in gotenberg from gotenberg. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 3.0% (higher than 87% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code.
Official description
Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.31.0, Gotenberg's /forms/pdfengines/metadata/write HTTP endpoint accepts a JSON metadata object and passes its keys directly to ExifTool via the go-exiftool library. No validation is performed on key characters. A \n embedded in a JSON key splits the ExifTool stdin stream into a new argument line, allowing an attacker to inject arbitrary ExifTool flags — including -if, which evaluates Perl expressions. This achieves unauthenticated OS command execution in a single HTTP request. The response is HTTP 200 with a valid PDF, making the attack transparent to basic monitoring. This vulnerability is fixed in 8.31.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/gotenberg/gotenberg/v7 | no fix listed | GO-2026-5636 |
| Go | github.com/gotenberg/gotenberg/v8 | no fix listed | GHSA-rqgh-gxv4-6657 |
| Go | github.com/gotenberg/gotenberg/v8 | no fix listed | GO-2026-5636 |
Affected products (as reported)
Weakness: CWE-78 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/gotenberg/gotenberg/security/advisories/GHSA-rqgh-gxv4-6657 x_refsource_CONFIRM