Gotenberg: Unauthenticated RCE via ExifTool Metadata Key Injection
85Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 9.8epss 3.0%
from disclosure to weapon16 days
Published on NVDMay 14
1st PoC+16d
VulnCheck+40d
exploitation probability
3.0%top 14% of all CVEs
observed exploitation
yesVulnCheck
2 public exploit(s)
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
gotenberg · gotenbergpublic PoCs found — 2
githubgithub.com/fineman999/POC_CVE-2026-42589★ 1vulncheckvulncheck.com/xdb/183f7a4a3dcaunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.