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.
Problem types
CWE-653 Improper Isolation or Compartmentalization
Product status
References
research.jfrog.com/...tion-mcp-takeover-jfsa-2026-001653030/