Description

FastMCP is the standard framework for building MCP applications. Prior to version 3.2.0, server names containing shell metacharacters (e.g., &) can cause command injection on Windows when passed to fastmcp install claude-code or fastmcp install gemini-cli. These install paths use subprocess.run() with a list argument, but on Windows the target CLIs often resolve to .cmd wrappers that are executed through cmd.exe, which interprets metacharacters in the flattened command string. This issue has been patched in version 3.2.0.

INFO

Published Date :

2026-04-03T15:16:13.930Z

Last Modified :

2026-04-03T16:12:58.401Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-64340 vulnerability.

Vendors Products
Jlowin
  • Fastmcp
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-64340.

URL Resource
https://github.com/PrefectHQ/fastmcp/pull/3522 cve-icon cve-icon
https://github.com/PrefectHQ/fastmcp/security/advisories/GHSA-m8x7-r2rg-vh5g cve-icon cve-icon cve-icon
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