CVE-2025-64340
FastMCP has a Command Injection vulnerability - Gemini CLI
Vexday Risk Score
13Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 6.7EPSS 0.7%KEV nãoPoC —Nuclei —Metasploit —Patch —
Lifecycle
03 Apr 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
Affected products
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