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...

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...

PT-2026-60671

Summary In affected versions, the deprecated WebSocket server transport mcp.server.websocket.websocket server 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...