# CVE-2026-42589: Gotenberg OS command injection in PDF metadata write endpoint

Source: https://junglewise.ai/threats/cve-2026-42589-gotenberg-os-command-injection-in-pdf-metadata-write-endpoint  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-14. Updated: 2026-05-18  
License: CC BY 4.0 with a link back

CVE-2026-42589 · Severity: critical · CVSS 9.8 · Published 2026-05-14

Gotenberg is a tool used to convert various documents into PDF files via a web interface. A security flaw allows an unauthenticated attacker to execute malicious commands on the server by sending a specially crafted request to the metadata editing feature. This could lead to a total system takeover, data theft, or a foothold for further attacks within a corporate network, all while appearing as a successful, normal document process to monitoring tools.

Technologies: [github.com/gotenberg/gotenberg/v7 (Go)](https://junglewise.ai/threats/technologies/github-com-gotenberg-gotenberg-v7), [github.com/gotenberg/gotenberg/v8 (Go)](https://junglewise.ai/threats/technologies/github-com-gotenberg-gotenberg-v8), [Gotenberg](https://junglewise.ai/threats/technologies/gotenberg). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Gotenberg](https://junglewise.ai/threats/vendors/gotenberg).

## Quick answers

**Is CVE-2026-42589 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42589 being exploited in the wild.

**How severe is CVE-2026-42589?** Critical severity, with a CVSS score of 9.8, 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) = 8.29.1, SEMVER:introduced=0; Gotenberg < 8.31.0, 8.29.1.

**Is there a fix for CVE-2026-42589?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-42589 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-42589?** 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

The vulnerability exists in the /forms/pdfengines/metadata/write endpoint of Gotenberg. The application accepts a JSON metadata object and passes its keys to ExifTool via the go-exiftool library without validating for control characters. An attacker can embed a newline character (\n) in a JSON key, which causes the go-exiftool library to split the input into multiple argument lines when writing to ExifTool's stdin. This allows the injection of arbitrary ExifTool flags, such as '-if', which evaluates Perl expressions. By injecting a Perl 'system()' call, an unauthenticated remote attacker can achieve OS command execution. The attack is particularly stealthy as the server returns an HTTP 200 status and a valid PDF file even when the exploit is successful. The issue is resolved in version 8.31.0.

## Affected products

- Gotenberg Gotenberg < 8.31.0

## Identifiers

- CVE-2026-42589
- GHSA-rqgh-gxv4-6657
- GO-2026-5636

## Timeline

- 2026-04-30: advisory: GitHub Security Advisory published
- 2026-05-14: disclosed: CVE published to NVD

## References

- [https://github.com/gotenberg/gotenberg/security/advisories/GHSA-rqgh-gxv4-6657](https://github.com/gotenberg/gotenberg/security/advisories/GHSA-rqgh-gxv4-6657)

## Related threats

- [Gotenberg server-side request forgery in IsPublicIP IPv6 handling](https://junglewise.ai/threats/cve-2026-126799-gotenberg-8-31-0-before-8-38-0-contains-a-server-side-request)
- [Gotenberg race condition in multipart downloadFrom handling](https://junglewise.ai/threats/cve-2026-45742-gotenberg-race-condition-in-multipart-downloadfrom-handling)
- [Gotenberg SSRF deny-list bypass in IsPublicIP via IPv6 prefixes](https://junglewise.ai/threats/cve-2026-45741-gotenberg-ssrf-deny-list-bypass-in-ispublicip-via-ipv6-prefixes)
- [Gotenberg path traversal via Windows-style separators in ZIP entry names](https://junglewise.ai/threats/cve-2026-44829-gotenberg-path-traversal-via-windows-style-separators-in-zip)
- [Gotenberg SSRF and local file disclosure in LibreOffice conversion](https://junglewise.ai/threats/cve-2026-55229-gotenberg-ssrf-and-local-file-disclosure-in-libreoffice)