PoC Index

CVE-2025-64340

HIGH 7.8EPSS 0.7%

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.

CVSS v3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v3.1
6.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
CVSS v3.1
6.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS
0.73% chance of exploitation in the next 30 days, 52th percentile
Published
2026-04-03

Proof-of-concept exploits (1)

References

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