Description

The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.9.4, a validation error in the MCP SDK can cause an unhandled exception when processing malformed requests, resulting in service unavailability (500 errors) until manually restarted. Impact may vary depending on the deployment conditions, and presence of infrastructure-level resilience measures. Version 1.9.4 contains a patch for the issue.

INFO

Published Date :

2025-07-04T22:05:02.975Z

Last Modified :

2025-07-04T22:05:02.975Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-53366 vulnerability.

No data.

REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-53366.

URL Resource
https://github.com/modelcontextprotocol/python-sdk/commit/29c69e6a47d0104d0afcea6ac35e7ab02fde809a cve-icon cve-icon
https://github.com/modelcontextprotocol/python-sdk/pull/822 cve-icon cve-icon
https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-3qhf-m339-9g5v cve-icon cve-icon
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