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.
References (3)
Scores
CVSS v4
8.7
EPSS
0.0014
EPSS Percentile
33.9%
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
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-248
Status
published
Products (2)
modelcontextprotocol/python-sdk
< 1.10.0
pypi/mcp
0 - 1.10.0PyPI
Published
Jul 04, 2025
Tracked Since
Feb 18, 2026