Vulnerability in ONLYOFFICE DocumentServer

[ Description ]Official description

ONLYOFFICE DocumentServer before 10.0.0 contains an unauthenticated server-side request forgery vulnerability in the /downloadfile/:docid endpoint that allows remote attackers to bypass the private-IP request-filtering-agent by exploiting the isInJwtToken flag when JWT verification is disabled in the default configuration. Attackers can submit a crafted request body containing an internal or loopback URL, which is treated as a DIRECT request skipping private-address filtering, causing the server to fetch and proxy back arbitrary private-network and cloud metadata content.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund14 Oct 2026WID-SEC-2026-3961

  ONLYOFFICE Docs: Vulnerability allows information disclosure Translated from German

  CVE-2026-110652

[ References ]References

• github.com/ONLYOFFICE/DocumentServer/blob/master/CHANGELOG.md
• github.com/ONLYOFFICE/DocumentServer/releases/tag/v10.0.0
• www.vulncheck.com/advisories/onlyoffice-documentserver-before-ssrf-via-downloadfile-isi…