ONLYOFFICE Docs Server Path Traversal Vulnerability

ONLYOFFICE Docs

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. Added to CISA KEV on 2026-10-08 (federal deadline 2026-10-11).

First seen: 8 Oct 2026
Last update: 8 Oct 2026, 12:00 UTC
Identifiers: CVE-2021-3199
CVSS: 9.8
Source: CISA KEV

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## ONLYOFFICE Docs Server Path Traversal Vulnerability
Severity: critical, exploited in the wild. Patch status: patched.
Affected: ONLYOFFICE Docs
Ids: CVE-2021-3199

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. Added to CISA KEV on 2026-10-08 (federal deadline 2026-10-11).

## Steps
1. Search the repo, its CI and infra config for ONLYOFFICE Docs. If present, report the version in use and whether it's affected.

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve("CVE-2021-3199") for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://github.com/ONLYOFFICE/DocumentServer/blob/903fe5ab7a275bd69c3c3346af2d21cf87ebeabf/CHANGELOG.md#563 https://nvd.nist.gov/vuln/detail/CVE-2021-3199
https://pwned.coffee/i/onlyoffice-docs-server-path-traversal-vulnerability-cve-2021-3199

Sources

Totalone very hot coffee