FKIE_CVE-2026-25905

Vulnerability from fkie_nvd - Published: 2026-02-09 09:16 - Updated: 2026-02-09 16:08
Severity ?
5.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L
Summary
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
reefs@jfrog.comhttps://research.jfrog.com/vulnerabilities/mcp-run-python-lack-of-isolation-mcp-takeover-jfsa-2026-001653030/
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Python code being run by \u0027runPython\u0027 or \u0027runPythonAsync\u0027 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."
    },
    {
      "lang": "es",
      "value": "El c\u00f3digo Python ejecutado por \u0027runPython\u0027 o \u0027runPythonAsync\u0027 no est\u00e1 aislado del resto del c\u00f3digo JS, permitiendo que cualquier c\u00f3digo Python utilice las API de Pyodide para modificar el entorno JS. Esto puede resultar en que un atacante secuestre el servidor MCP - con fines maliciosos, incluida la suplantaci\u00f3n de herramientas MCP. Nota - el proyecto \"mcp-run-python\" est\u00e1 archivado y es poco probable que reciba una soluci\u00f3n."
    }
  ],
  "id": "CVE-2026-25905",
  "lastModified": "2026-02-09T16:08:35.290",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 3.7,
        "source": "reefs@jfrog.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-02-09T09:16:34.030",
  "references": [
    {
      "source": "reefs@jfrog.com",
      "url": "https://research.jfrog.com/vulnerabilities/mcp-run-python-lack-of-isolation-mcp-takeover-jfsa-2026-001653030/"
    }
  ],
  "sourceIdentifier": "reefs@jfrog.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-653"
        }
      ],
      "source": "reefs@jfrog.com",
      "type": "Primary"
    }
  ]
}


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