CVE-2025-53365 – mcp

Package

Manager: pip
Name: mcp
Vulnerable Version: >=0 <1.10.0

Severity

Level: High

CVSS v3.1: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:U/RC:C

CVSS v4.0: 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: 0.00057 pctl0.178

Details

MCP Python SDK has Unhandled Exception in Streamable HTTP Transport, Leading to Denial of Service 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. Thank you to Rich Harang for reporting this issue.

Metadata

Created: 2025-07-04T22:06:31Z
Modified: 2025-07-05T01:45:45Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/07/GHSA-j975-95f5-7wqh/GHSA-j975-95f5-7wqh.json
CWE IDs: ["CWE-248"]
Alternative ID: GHSA-j975-95f5-7wqh
Finding: F140
Auto approve: 1