CVE-2025-53365
The MCP Python SDK, called `mcp` on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.10.0, if a client deliberately triggers an exception after establishing a streamable HTTP session, this can lead to an uncaught ClosedResourceError on the server side, causing the server to crash and requiring a restart to restore service. Impact may vary depending on the deployment conditions, and presence of infrastructure-level resilience measures. Version 1.10.0 contains a patch for the issue.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.7
- CVSS vector
- 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
- EPSS probability
- 0.36%
- CWE
- CWE-248
- Published
- 2025-07-04
- Last modified
- 2026-03-13
Affected products
- modelcontextprotocol python-sdk
Weakness type
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