---
id: CVE-2025-62801
title: FastMCP is the standard framework for building MCP applications
summary: >-
  FastMCP is the standard framework for building MCP applications. Versions
  prior to 2.13.0, a command-injection vulnerability lets any attacker who can
  influence the server_name field of an MCP execute arbitrary OS commands on
  Windows hos…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-78
vendor: jlowin
product: fastmcp
affected:
  - fastmcp < 2.13.0
patched:
  - fastmcp 2.13.0
published: '2025-10-28'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T11:10:00.250'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-62801'
references:
  - url: 'https://github.com/jlowin/fastmcp/security/advisories/GHSA-rj5c-58rq-j5g5'
    label: security-advisories@github.com
  - url: 'https://github.com/jlowin/fastmcp/security/advisories/GHSA-rj5c-58rq-j5g5'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-62801'
  - url: 'https://github.com/jlowin/fastmcp'
tags:
  - nvd
  - osv
  - pip
epss: 0.00227
epssPercentile: 0.13389
aliases:
  - GHSA-rj5c-58rq-j5g5
  - PYSEC-2026-1365
ecosystem: pip
ingestedAt: '2026-07-08T18:25:52.741Z'
---

## Overview

FastMCP is the standard framework for building MCP applications. Versions prior to 2.13.0, a command-injection vulnerability lets any attacker who can influence the server_name field of an MCP execute arbitrary OS commands on Windows hosts that run fastmcp install cursor. This vulnerability is fixed in 2.13.0.

## Affected

- `fastmcp < 2.13.0`

## Remediation

Upgrade past the affected range:

- `fastmcp 2.13.0`

## Package advisory (CVE-2025-62801)

Affected packages:

- `fastmcp < 2.13.0`

Patched in:

- `fastmcp 2.13.0`

Source: https://osv.dev/vulnerability/GHSA-rj5c-58rq-j5g5