CVE-2025-53365
MCP Python SDK has Unhandled Exception in Streamable HTTP Transport ,Leading to Denial of Service
- State
- Published
- Severity
- 8.7 High
- Published
- Jul 4, 2025
- Updated
- Jul 8, 2025
- Reserved
- Jun 27, 2025
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 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 | GitHub_M |
Weaknesses
- CWE-248 Uncaught Exception
Affected Products
| Product | Versions |
|---|---|
python-sdkmodelcontextprotocol |
|
References
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