GHSA-VJ7Q-GJH5-988W MCP Python SDK: WebSocket server transport does not support Host/Origin validation

Summary In affected versions, the deprecated WebSocket server transport mcp.server.websocket.websocketserver accepted the WebSocket handshake without applying any Host or Origin header validation. The TransportSecuritySettings mechanism that the SSE and Streamable HTTP transports use for this...

EUVD-2026-44798

MCP Python SDK: WebSocket server transport does not support Host/Origin validation...

CVE-2026-59950 MCP Python SDK: WebSocket server transport does not support Host/Origin validation

The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol MCP. Prior to 1.28.1, the deprecated mcp.server.websocket.websocketserver transport accepted WebSocket handshakes without applying Host or Origin header validation, leaving no SDK-level way to restric...