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

CVE ID :CVE-2026-59950

Published : July 15, 2026, 9:16 p.m. | 17 minutes ago

Description :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.websocket_server transport accepted WebSocket handshakes without applying Host or Origin header validation, leaving no SDK-level way to restrict which origins could connect to applications that exposed that transport. This issue is fixed in version 1.28.1.

Severity: 7.6 | HIGH

Visit the link for more details, such as CVSS details, affected products, timeline, and more…