CVE-2026-84282

A Server-Side Request Forgery (SSRF) vulnerability exists in the ONLYOFFICE ownCloud Integration plugin version 9.12. The /apps/onlyoffice/ajax/settings/address endpoint does not sufficiently validate the user-supplied Document Server URL before initiating outbound connections. An authenticated administrator can manipulate the document server parameter to cause the ownCloud server to send arbitrary requests to attacker-controlled destinations, including localhost and internal network hosts. This allows internal network reconnaissance and TCP port scanning based on differences in server responses.

• https://github.com/ONLYOFFICE/onlyoffice-owncloud/blob/master/controller/settingsapicontroller.php
• https://kb.cert.org/vuls/id/943094
• https://www.kb.cert.org/vuls/id/943094