---
title: "CVE-2026-42589: Gotenberg has Unauthenticated RCE via ExifTool Metadata Key Injection"
url: https://erroneo.us/security/cve/CVE-2026-42589/
description: "CVE-2026-42589 (github.com/gotenberg/gotenberg/v8 (Go)): Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.31.0, Gotenberg's…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-05-14
date_modified: 2026-05-14
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-42589"
kev: false
cvss: 9.8
epss: 0.03675
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-42589: Gotenberg has Unauthenticated RCE via ExifTool Metadata Key Injection

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 3.7% , percentile 90: FIRST’s model estimates a 3.7% chance of exploitation activity in the next 30 days, higher than 90% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes github.com/gotenberg/gotenberg/v8 (Go) = 8.29.1, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

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

- Go `github.com/gotenberg/gotenberg/v8` = 8.29.1 → fixed: none listed

## Affected products (CVE record)

- gotenberg gotenberg: < 8.31.0

## Severity

- GitHub_M CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 3.67% probability of exploitation activity in the next 30 days; percentile 90.

## Sources

- [GitHub Advisory GHSA-rqgh-gxv4-6657](https://github.com/advisories/GHSA-rqgh-gxv4-6657)
- [CVE.org record CVE-2026-42589](https://www.cve.org/CVERecord?id=CVE-2026-42589)
- [NVD entry CVE-2026-42589](https://nvd.nist.gov/vuln/detail/CVE-2026-42589)
- [github.com](https://github.com/gotenberg/gotenberg/security/advisories/GHSA-rqgh-gxv4-6657)

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Source page: https://erroneo.us/security/cve/CVE-2026-42589/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt