RCE in Gotenberg
CVE-2026-42589
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.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.037 (89.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.030 · newest: 0.037 · change: +0.007
Affected products
- Gotenberg — versions < 8.31.0
- Thecodingmachine Gotenberg
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/gotenberg/gotenberg/security/advisories/GHSA-rqgh-gxv4-6657 (Exploit, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42589?
- CVE-2026-42589 is a critical-severity vulnerability in Gotenberg, classified under OS Command Injection. CVSS score: 9.8/10. Published 2026-05-14.
- How severe is CVE-2026-42589?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2026-42589 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.