CVE-2021-3199
Server Path Traversal in ONLYOFFICE Docs. CISA confirmed attackers exploit it and added it to its Known Exploited Vulnerabilities catalog on 8 October 2026.
- Product
- ONLYOFFICE Docs
- Added to CISA's catalog
- Federal fix-by date
- Ransomware
- No known use in ransomware campaigns
- Vendor advisories
- Sources
- CISA’s catalog, NVD entry
CISA’s 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.
Every flaw CISA confirmed exploited in the last 30 days is on the exploit watch. This is not security advice. Check the vendor’s advisory before acting. From CISA’s catalog of 4 November 2026.