CVE-2025-53366 (GCVE-0-2025-53366)
Vulnerability from cvelistv5
Published
2025-07-04 22:05
Modified
2025-07-08 13:52
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
Summary
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.
References
security-advisories@github.comhttps://github.com/modelcontextprotocol/python-sdk/commit/29c69e6a47d0104d0afcea6ac35e7ab02fde809a
security-advisories@github.comhttps://github.com/modelcontextprotocol/python-sdk/pull/822
security-advisories@github.comhttps://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-3qhf-m339-9g5v
Impacted products
Vendor Product Version
modelcontextprotocol python-sdk Version: < 1.9.4
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