Uncaught Exception Affecting mcp package, versions [,1.10.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.05% (17th percentile)

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  • Snyk IDSNYK-PYTHON-MCP-10734136
  • published14 Jul 2025
  • disclosed4 Jul 2025
  • creditRich Harang

Introduced: 4 Jul 2025

NewCVE-2025-53365  (opens in a new tab)
CWE-248  (opens in a new tab)

How to fix?

Upgrade mcp to version 1.10.0 or higher.

Overview

mcp is a Model Context Protocol SDK

Affected versions of this package are vulnerable to Uncaught Exception via the _receive_loop function in the shared/session.py file. An attacker can cause the server to crash and require a restart by deliberately triggering an exception after establishing a streamable HTTP session.

CVSS Base Scores

version 4.0
version 3.1