Description
FastMCP is the standard framework for building MCP applications. Prior to version 3.2.0, while testing the GitHubProvider OAuth integration, which allows authentication to a FastMCP MCP server via a FastMCP OAuthProxy using GitHub OAuth, it was discovered that the FastMCP OAuthProxy does not properly validate the user-s consent upon receiving the authorization code from GitHub. In combination with GitHub-s behavior of skipping the consent page for previously authorized clients, this introduces a Confused Deputy vulnerability. This issue has been patched in version 3.2.0.
CVSS 6.1EPSS 0.207%Risk 0.62
View source- Published
- 2026-04-03 16:16:36
- Affected versions
- <3.2.0
- Type
- Package
- Last modified
- 2026-07-24 22:10:00
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N