CVE-2026-59950: fallo de gravedad alta en modelcontextprotocol python-sdk
MCP Python SDK: WebSocket server transport does not support Host/Origin validation
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.6epss 0.2%
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.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Productos afectados
modelcontextprotocol · python-sdkCVEs relacionadas — modelcontextprotocol python-sdk
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Referencias
https://github.com/modelcontextprotocol/python-sdk/commit/777b8d06710c140e3606b0d4598e2aa48546c266https://github.com/modelcontextprotocol/python-sdk/pull/2992https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.28.1https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-vj7q-gjh5-988w