Vulnerability · Published Sep 8, 2026 · Assigned by certcc
CVE-2026-84282A Server-Side Request Forgery (SSRF) vulnerability exists in the ONLYOFFICE ownCloud Integration plugin (version 9.12)
Medium 6.5
In plain English
A medium-severity security flaw in ONLYOFFICE ownCloud integration plugin from Ascensio System SIA / OnlyOffice. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Ascensio System SIA / OnlyOffice | ONLYOFFICE ownCloud integration plugin | 9.12 |