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.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - 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.
    (CVE-2026-59950)

ID	Name	Product	Family	Type	Severity
457041	Echo: mcp: security update to 1.28.1	Tenable Cloud Security	Echo Local Security Checks	Local	high
457041	Echo: mcp: security update to 1.28.1	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	high
444802	SCA: security update for mcp (GHSA-vj7q-gjh5-988w)	Tenable Cloud Security	SCA Checks	Local	high
444802	SCA: security update for mcp (GHSA-vj7q-gjh5-988w)	Tenable Self-Hosted Container Security	SCA Checks	Local	high

Detections

Analytics

CVE-2026-59950

high

Tenable Plugins

high

high

high

high