CVE-2025-64340 (GCVE-0-2025-64340)

Vulnerability from cvelistv5 – Published: 2026-04-03 15:16 – Updated: 2026-04-03 16:12
VLAI
Title
FastMCP has a Command Injection vulnerability - Gemini CLI
Summary
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.
Severity
6.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-03 16:11 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7711 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
jlowin fastmcp Affected: < 3.2.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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