CVE-2026-39974

Estado: AnalizadaAlta (8.5)—

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.

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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.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
Puntuación base: 8.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.43%
Percentil entre todas las CVEs puntuadas: 35
Fecha de la puntuación: 6/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement90 %
Impacto principalT1090.003 Multi-hop Proxycommand and control85 %
Impacto secundarioT1005 Data from Local Systemcollection80 %

SSRF autenticado (PR:L) en servidor remoto: T1210. Impactos: proxy/túnel SSRF (T1090.003) para alcanzar metadatos en la nube e interno; lectura de datos (T1005) de respuestas HTTP reflejadas en JSON-RPC.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability Scanning Threat Intelligence Program Privileged Account Management Network Segmentation Filter Network Traffic Disable or Remove Feature or Program

Tecnologías afectadas (1)

N8n-mcp — N8n-mcp

CWE

CWE-918

Referencias

JSON original (NVD)

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