CVE-2025-64340
MediumCVSS 6.7Exploitation Probability (EPSS)
Elevated risk51th percentile - higher than 51% of all known CVEs
Summary
A vulnerability in FastMCP before version 3.2.0. Server names containing shell metacharacters (e.g., &) can cause command injection on Windows during installation via fastmcp install claude-code or gemini-cli.
Risk Assessment
An attacker can exploit this to execute arbitrary commands on Windows, potentially leading to application compromise.
Recommendation
Upgrade FastMCP to version 3.2.0 or later.
Original NVD description (English source)
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.