CVE-2026-42589
CriticalExploitedPublic exploitGotenberg has Unauthenticated RCE via ExifTool Metadata Key Injection
Published May 7, 2026 · Updated Aug 12, 2026 · Also known as GHSA-rqgh-gxv4-6657, GO-2026-5636
Key Facts
Patch immediately- CVE-2026-42589 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Gotenberg (Thecodingmachine), github.com/gotenberg/gotenberg/v7 (go), github.com/gotenberg/gotenberg/v8 (go).
- It is exploited in the wild, listed in Industry KEV feed since Jun 23, 2026. Public exploit code is available.
- EPSS estimates a 3.7% probability of exploitation in the next 30 days.
- Fixed versions are available, including Gotenberg 8.31.0.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
3.7%
Higher than 89.5% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
Available
Proof-of-concept or weaponized module
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Jun 23, 2026 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
4 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| GotenbergThecodingmachine | >= < 8.31.0 | 8.31.0 |
| github.com/gotenberg/gotenberg/v7go | See advisory | n/a |
| github.com/gotenberg/gotenberg/v8go | >= 8.29.1 | n/a |
Patched Releases
Gotenberg
8.31.0
Timeline
Publicly disclosed
May 7, 2026
Added to Industry KEV feed
Jun 23, 2026
Last updated
Aug 12, 2026
Weakness Type
- CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
References
FAQ
Common Questions.
Gotenberg is a Docker-powered stateless API for PDF files.
Affected: Gotenberg (Thecodingmachine) versions >= < 8.31.0; github.com/gotenberg/gotenberg/v7 (go); github.com/gotenberg/gotenberg/v8 (go) versions >= 8.29.1. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Jun 23, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Gotenberg 8.31.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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