{"id":"ghsa-ghsa-5h93-6whr-6q8j","seq":1711759,"kind":"advisory","title":"Model Context Protocol Python SDK: HTTP client transports followed cross-origin redirects carrying custom headers and bodies","url":"https://github.com/advisories/GHSA-5h93-6whr-6q8j","permalink":"https://vulnpulse.app/items/ghsa-ghsa-5h93-6whr-6q8j","summary":"影響: pip:mcp >= 2.0.0, < 2.2.0 → 2.2.0, pip:mcp >= 1.8.0, < 1.30.0 → 1.30.0\nIn affected versions, the SDK's Streamable HTTP and SSE client transports followed HTTP redirects to any host. If the configured MCP endpoint answered with a redirect to a different origin: - custom headers set on the client (for example an X-API-Key credential) were sent to that origin, and - on a 307 or 308 redirect the request body was re-sent there too. The SDK's OAuth client providers followed redirects on their own discovery, registration and token requests in the same way. A lone Authori…","severity":"medium","techs":["python"],"cves":["CVE-2026-116685"],"tags":["GHSA-5h93-6whr-6q8j","mcp","mcp"],"source":{"id":"ghsa","name":"GitHub Advisory Database"},"published_at":"2026-10-27T21:05:34.000Z","fetched_at":"2026-10-27T21:17:52.472Z"}