Description
Gotenberg is a Docker-powered stateless API for PDF files. Prior to 8.31.0, the default deny-lists used by Gotenberg's downloadFrom feature and webhook feature are bypassable. Because the filter is regex-based and case-sensitive, an unauthenticated attacker can supply URLs such as http://[::ffff:127.0.0.1]:... and reach loopback or private HTTP services that the default deny-list is intended to block. This crosses a real security boundary because an external caller can force the server to make outbound requests to internal-only targets. This vulnerability is fixed in 8.31.0.
Affected products
thecodingmachine: gotenberg
References2
- github.com/gotenberg/gotenberg/security/advisories/GHSA-4vmc-gm… ExploitMitigationVendor Advisory
- github.com/gotenberg/gotenberg/security/advisories/GHSA-4vmc-gm… ExploitMitigationVendor Advisory
Metrics
- CVSS 3.1
-
9.4
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L - EPSS — exploit probability
- 2% percentile: 76 · as of 14 November 2026
- CWE
- CWE-918
Could this be exploited in your environment?
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