CVE-2026-25905

medium

Description

The Python code being run by 'runPython' or 'runPythonAsync' is not isolated from the rest of the JS code, allowing any Python code to use the Pyodide APIs to modify the JS environment. This may result in an attacker hijacking the MCP server - for malicious purposes including MCP tool shadowing. Note - the "mcp-run-python" project is archived and unlikely to receive a fix.

References

https://research.jfrog.com/vulnerabilities/mcp-run-python-lack-of-isolation-mcp-takeover-jfsa-2026-001653030/

Details

Source: Mitre, NVD

Published: 2026-02-09

Updated: 2026-02-09

Risk Information

CVSS v2

Base Score: 5.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:P

Severity: Medium

CVSS v3

Base Score: 5.8

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L

Severity: Medium