# CVE-2021-3199: A flaw in ONLYOFFICE Docs can let attackers take over the server

Status: Being used now (CISA KEV, added 2026-10-08)
Who: Organizations that host ONLYOFFICE Docs for shared editing.
Do this: Update ONLYOFFICE Docs to the latest version.

## Agent prompt (read-only)
Read-only check, change nothing, send nothing anywhere.
Is ONLYOFFICE Docs (CVE-2021-3199) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2021-3199. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.

## Official description
ONLYOFFICE Docs contains a path traversal vulnerability that can occur when JWT is used, via a /.. sequence in an image upload parameter and could allow for remote code execution.

## Sources
- https://github.com/ONLYOFFICE/DocumentServer/blob/903fe5ab7a275bd69c3c3346af2d21cf87ebeabf/CHANGELOG.md#563
- https://nvd.nist.gov/vuln/detail/CVE-2021-3199
- https://nvd.nist.gov/vuln/detail/CVE-2021-3199

Generated by isitexploited.org from public sources. Verify version numbers against the vendor before acting.