Vulnerability Database
290,476
Total vulnerabilities in the database
CVE-2025-53366
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.
| Software | From | Fixed in |
|---|---|---|
mcp
|
- | 1.9.4 |
- https://github.com/modelcontextprotocol/python-sdk/commit/29c69e6a47d0104d0afcea6ac35e7ab02fde809a
- https://github.com/modelcontextprotocol/python-sdk/pull/822
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.9.4
- https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-3qhf-m339-9g5v