Vulnerability report

Trusted Third Party Report High Confidence Not in CISA KEV

CVE-2026-42589

gotenberg Unauthenticated RCE Remote Code Execution

Gotenberg · affected before 8.31.0

Watch CVE-2026-42589 Browse KEV feed
Severity
CVSS 9.8 · Critical
Confidence
High
Exploit status
Trusted Third Party Report
EPSS
3.0%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-42589 is an unauthenticated vulnerability affecting gotenberg. Gotenberg is a Docker-powered stateless API for PDF files.

Have exploitation attempts been observed?

Yes. Exploitation attempts have been reported for this vulnerability. Previdian lists it as a known exploited vulnerability. Also reported by third-party sources. Confidence is high.

Who is affected?

gotenberg affected before 8.31.0.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Gotenberg is a Docker-powered stateless API for PDF files

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.

gotenberg Affected
gotenberg
Before 8.31.0
Published
14 May 2026
Exploitation Attempts Reported
31 Oct 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

nuclei_scanner

CVE References

Exploitation evidence

Evidence of exploitation attempts

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploitation Attempts Observed in the Wild

The Shadowserver

Recorded 31 Oct 2026

A trusted third party reported exploitation attempts.

Proof of concept available

GitHub

Recorded 30 May 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
The Shadowserver First 2026-10-31 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-42589.yaml 01 Jun 2026

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

3.0%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE-78

Recent mention · The Hacker News

ThreatsDay: Critical Firewall Flaws, Banking Trojans Rented, Weaponized PDF, Token Theft + 26 More Stories

Ravie LakshmananOct 29, 2026Hacking News / Cybersecurity News Some attacks take real skill. Others just need someone to leave a door open. This week has both. Exposed passwords, old bugs still getting exploited, and trusted software doing things it shouldn't. There's a...

Read full advisory

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Gotenberg - Command Injection

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation attempts

  1. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party report of exploitation attempts

  2. 14:21 UTC

    Public PoC available

    Public proof-of-concept code published

  3. 15:34 UTC

    Nuclei template available

    Scanner coverage available

  4. 15:11 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 00:31 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

Start 14-day Pro trial Read API docs
  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-42589

Sample API response 
{
  "cve_id": "CVE-2026-42589",
  "confidence": "High",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.03013,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}