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

Date Jul 16, 2026

Type Vendor advisory

Signal High-risk advisory

Vendor / Product PyPI · mcp

CVE CVE-2026-59950

High-risk advisory CVE-2026-59950

Summary

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

Why it matters

GitHub has published a reviewed security advisory for mcp. Prioritize it with other application dependency updates, especially because EPSS places it in the 8% percentile.

Operator check

Check whether mcp is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. CVSS score: 7.6. EPSS probability: 0.2%; percentile: 8%.

Sources

GitHub Advisory GHSA-vj7q-gjh5-988w NVD — CVE-2026-59950 Source reference

PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.

Get watched-vendor alerts Subscribe free Back to feed