Description

FastMCP is the standard framework for building MCP applications. Versions prior to 2.13.0 have a reflected cross-site scripting vulnerability in the OAuth client callback page (oauth_callback.py) where unescaped user-controlled values are inserted into the generated HTML, allowing arbitrary JavaScript execution in the callback server origin. The issue is fixed in version 2.13.0.

INFO

Published Date :

2025-10-28T21:34:40.392Z

Last Modified :

2025-10-28T21:34:40.392Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-62800 vulnerability.

Vendors Products
Fastmcp
  • Fastmcp
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-62800.

URL Resource
https://github.com/jlowin/fastmcp/security/advisories/GHSA-mxxr-jv3v-6pgc cve-icon cve-icon
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CVSS Vulnerability Scoring System

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