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CVE-2026-42235

Estado: AnalizadaAlta (8.8)—

n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an unauthenticated attacker could register a malicious MCP OAuth client with a crafted client_name. If a victim user authorized the OAuth consent dialog and a second user subsequently revoked that access, a toast notification would render the injected script. Clicking the link would execute arbitrary JavaScript in the victim's authenticated n8n browser session, enabling credential and session token theft, workflow manipulation, or privilege escalation. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.

CVSS

Probabilidad de explotación (EPSS)

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.

XSS en notificación toast tras revocación de OAuth (CWE-79). Inyección de script arbitrario en sesión autenticada: ejecución JS (T1059.007), robo de tokens/credenciales (T1552.007), acceso a cuenta (T1098.002).

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

Restrict Web-Based ContentPrivileged Account ManagementDisable or Remove Feature or ProgramUser TrainingUser Account ManagementNetwork Segmentation

Tecnologías afectadas (1)

N8N — N8N

CWE

Referencias

JSON original (NVD)

Mostrar
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  "lastModified": "2026-06-17T10:47:33.523",
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