## FastMCP: Post-transform component authorization is skipped on direct calls

- 種別: advisory
- 重大度: medium
- 関連技術: python
- 公開日時: 2026-10-23T21:32:06.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-7xgj-8392-5q4r)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-7xgj-8392-5q4r

影響: pip:fastmcp >= 3.0.0, < 3.4.10 → 3.4.10, pip:fastmcp >= 4.0.0, < 4.1.2 → 4.1.2, pip:fastmcp-slim >= 3.0.0, < 3.4.10 → 3.4.10, pip:fastmcp-slim >= 4.0.0, < 4.1.2 → 4.1.2
Maintainer assessment and remediation This report is accepted as a FastMCP authorization vulnerability. In supported configurations, a server transform can change the metadata used by a component's authorization policy. Direct lookups previously checked the original component but returned the transformed component without rechecking its policy. A client that knows the component identifier can invoke a tool or retrieve a resource or prompt that the configured policy denies. The fixes authorize t…