GHSA-rcfx-77hg-w2wv
FastMCP updated to MCP 1.23+ due to CVE-2025-66416
There was a recent CVE report on MCP: https://nvd.nist.gov/vuln/detail/CVE-2025-66416.
FastMCP does not use any of the affected components of the MCP SDK directly. However, FastMCP versions prior to 2.14.0 did allow MCP SDK versions <1.23 that were vulnerable to CVE-2025-66416. Users should upgrade to FastMCP 2.14.0 or later.
What each source reports
GitHub AdvisoriesNo score
FastMCP updated to MCP 1.23+ due to CVE-2025-66416
There was a recent CVE report on MCP: https://nvd.nist.gov/vuln/detail/CVE-2025-66416.
FastMCP does not use any of the affected components of the MCP SDK directly. However, FastMCP versions prior to 2.14.0 did allow MCP SDK versions <1.23 that were vulnerable to CVE-2025-66416. Users should upgrade to FastMCP 2.14.0 or later.
- Record
GHSA-rcfx-77hg-w2wv- Updated
- 2026-11-02
OSVNo score
FastMCP updated to MCP 1.23+ due to CVE-2025-66416
There was a recent CVE report on MCP: https://nvd.nist.gov/vuln/detail/CVE-2025-66416.
FastMCP does not use any of the affected components of the MCP SDK directly. However, FastMCP versions prior to 2.14.0 did allow MCP SDK versions <1.23 that were vulnerable to CVE-2025-66416. Users should upgrade to FastMCP 2.14.0 or later.
- Record
GHSA-rcfx-77hg-w2wv- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
fastmcpPyPI | before 2.14.0 | 2.14.0 |
fastmcpPyPI | before 2.14.0, plus listed versions 0.1.00.2.00.3.00.3.10.3.2 Show 45 moreShow less0.3.30.3.40.3.50.4.00.4.11.02.0.02.1.02.1.12.1.22.10.02.10.12.10.22.10.32.10.42.10.52.10.62.11.02.11.12.11.22.11.32.12.02.12.0rc12.12.12.12.22.12.32.12.42.12.52.13.02.13.0.12.13.0.22.13.0rc12.13.0rc22.13.0rc32.13.12.13.22.13.32.2.02.2.12.2.102.2.22.2.32.2.42.2.52.2.6 | 2.14.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-rcfx-77hg-w2wv is a vulnerability with no CVSS score yet in fastmcp, published December 26, 2025. No source lists public exploit code. Fixed in fastmcp 2.14.0.
References
Left out here: 23 versions. The JSON record has them.