CVE-2026-9780

Estado: AnalizadaAlta (8.8)—

Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability. This vulnerability allows remote attackers to bypass authentication on affected installations of Quest NetVault Backup. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the addclient3 webpage. The issue results from the lack of proper validation of user-supplied data, which can lead to the injection of an arbitrary script. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-27666.

CVSS

Versión: 3.0
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Puntuación base: 8.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.94%
Percentil entre todas las CVEs puntuadas: 60
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.

ExplotaciónT1189 Drive-by Compromiseinitial access95 %
Impacto principalT1078 Valid Accountsstealth · persistence · privilege escalation · initial access85 %
Impacto secundarioT1059 Command and Scripting Interpreterexecution75 %

XSS en página web (CWE-79) con interacción del usuario → T1189. Bypass de autenticación (T1078) + ejecución de código arbitrario en SYSTEM (impacto secundario T1059), aunque se menciona 'script' de forma genérica, no JavaScript específico del navegador.

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

User Training Restrict Web-Based Content Privileged Account Management Application Developer Guidance Active Directory Configuration User Account Management

Tecnologías afectadas (1)

Quest — Netvault Backup

CWE

CWE-79

Referencias

JSON original (NVD)

Mostrar

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