Gotenberg - SSRF (CVE-2026-55229)

CVE-2026-55229 is a high-severity server-side request forgery (SSRF) vulnerability in Gotenberg versions prior to 8.34.0. A specially crafted document processed through the LibreOffice conversion endpoint can force the service to retrieve external HTTP(S) resources or local files, enabling blind SSRF attacks and limited local file disclosure.

CrowdSec has been tracking this vulnerability and its exploits since 17th of September 2026.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2026-55229 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting. Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2026-55229 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2026-55229 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers target the /forms/libreoffice/convert endpoint by uploading a crafted DOCX containing external relationships that reference local files or remote URLs. Successful exploitation may cause LibreOffice to fetch and embed these resources in a generated PDF, enabling limited local file disclosure or blind SSRF.