CVEvulnerability

CVE-2025-64340

7.8 HIGH Published 2026-04-03 Modified 2026-07-24 Official page ↗
Status
Analyzed
Published
2026-04-03
Last modified
2026-07-24
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.7 MEDIUM — CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
CVSS 3.1 ([email protected])
7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weaknesses
CWE-78

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.

Affected configurations

• jlowin fastmcp (< 3.2.0)

Related

Weakness · CWE (1)

  • CWE-78 Improper Neutralization of Special Elements used in an OS Command weakness

References