CVE-2026-39974

{
  "id": "CVE-2026-39974",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-09T17:16:30.933",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "n8n-MCP is a Model Context Protocol (MCP) server that provides AI assistants with comprehensive access to n8n node documentation, properties, and operations. Prior to 2.47.4, an authenticated Server-Side Request Forgery in n8n-mcp allows a caller holding a valid AUTH_TOKEN to cause the server to issue HTTP requests to arbitrary URLs supplied through multi-tenant HTTP headers. Response bodies are reflected back through JSON-RPC, so an attacker can read the contents of any URL the server can reach — including cloud instance metadata endpoints (AWS IMDS, GCP, Azure, Alibaba, Oracle), internal network services, and any other host the server process has network access to. The primary at-risk deployments are multi-tenant HTTP installations where more than one operator can present a valid AUTH_TOKEN, or where a token is shared with less-trusted clients. Single-tenant stdio deployments and HTTP deployments without multi-tenant headers are not affected. This vulnerability is fixed in 2.47.4."
    },
    {
      "lang": "es",
      "value": "n8n-MCP es un servidor de Protocolo de Contexto de Modelo (MCP) que proporciona a los asistentes de IA acceso completo a la documentación, propiedades y operaciones de los nodos de n8n. Antes de la versión 2.47.4, una falsificación de petición del lado del servidor autenticada en n8n-mcp permite a un llamador que posee un AUTH_TOKEN válido hacer que el servidor emita peticiones HTTP a URLs arbitrarias suministradas a través de cabeceras HTTP multi-inquilino. Los cuerpos de respuesta se reflejan a través de JSON-RPC, por lo que un atacante puede leer el contenido de cualquier URL a la que el servidor pueda acceder, incluyendo puntos finales de metadatos de instancias en la nube (AWS IMDS, GCP, Azure, Alibaba, Oracle), servicios de red internos y cualquier otro host al que el proceso del servidor tenga acceso de red. Las implementaciones principales en riesgo son las instalaciones HTTP multi-inquilino donde más de un operador puede presentar un AUTH_TOKEN válido, o donde un token se comparte con clientes menos confiables. Las implementaciones stdio de un solo inquilino y las implementaciones HTTP sin cabeceras multi-inquilino no se ven afectadas. Esta vulnerabilidad está corregida en la versión 2.47.4."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "czlonkowski",
          "product": "n8n-mcp",
          "versions": [
            {
              "version": "< 2.47.4",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N",
          "baseScore": 8.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 4.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-13T20:09:16.284220Z",
          "id": "CVE-2026-39974",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:n8n-mcp:n8n-mcp:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "2.47.4",
              "matchCriteriaId": "7CAAB9F8-4304-40CE-8A09-81BCE0D42741"
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  "references": [
    {
      "url": "https://github.com/czlonkowski/n8n-mcp/commit/d9d847f230923d96e0857ccecf3a4dedcc9b0096",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.47.4",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-4ggg-h7ph-26qr",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}