Threats tagged 'ghsa-5h93-6whr-6q8j'

The Model Context Protocol (MCP) Python SDK versions 1.8.0 through 1.29.1 and 2.0.0 through 2.1.1 have a vulnerability where their HTTP client transports follow cross-origin HTTP redirects and send custom headers and request bodies to the redirected host. This behavior can expose sensitive headers such as API keys if the trusted endpoint redirects to an attacker-controlled domain. The SDK's OAuth client providers are similarly affected. The lone Authorization bearer header is not exposed due to existing HTTP library protections. The issue is fixed in MCP versions 1.30.0 and 2.2.0 by restricting redirects to the same origin only and failing otherwise.