Is fastmcp affected by CVE-2025-62800?

PyPI fastmcp is affected in <2.13.0.

Is CVE-2025-62800 being exploited?

Not on the CISA KEV list. EPSS exploit probability is 0.2%.

medium

CVE-2025-62800

Q: Is CVE-2025-62800 being exploited?

Not on the CISA KEV list. EPSS exploit probability is 0.2%.

PyPI · fastmcp

Summary

FastMCP vulnerable to reflected XSS in client's callback page

Severity: medium
EPSS: 0.2% (p13)
Also known as: GHSA-mxxr-jv3v-6pgc
Published: 2025-10-29

References

https://github.com/jlowin/fastmcp/security/advisories/GHSA-mxxr-jv3v-6pgc
https://nvd.nist.gov/vuln/detail/CVE-2025-62800
https://github.com/jlowin/fastmcp/pull/2090

Related advisories

CVE-2026-32871 — critical · PyPI/fastmcp
CVE-2026-27124 — high · PyPI/fastmcp
CVE-2025-69196 — high · PyPI/fastmcp
GHSA-rcfx-77hg-w2wv — high · PyPI/fastmcp
GHSA-c2jp-c369-7pvx — high · PyPI/fastmcp
CVE-2025-64340 — medium · PyPI/fastmcp
CVE-2025-62801 — medium · PyPI/fastmcp

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Sources: CISA KEV (public domain), OSV.dev & GitHub Advisory Database (CC-BY-4.0), FIRST EPSS, NVD/CWE (public domain). Served live from the Stateward advisory database.