CVE-2026-42596

CRITICAL

Gotenberg: Unauthenticated SSRF via default deny-list bypass in downloadFrom and webhook

Title source: cna
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 9.4
EPSS 0.0035
EPSS Percentile 26.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-918
Status published
Products (3)
gotenberg/gotenberg 0 - 8.32.0Go
gotenberg/gotenberg < 8.31.0
thecodingmachine/gotenberg < 8.31.0
Published May 14, 2026
Tracked Since May 14, 2026