CVE-2025-34520

Estado: AnalizadaAlta (7.7)—

An authentication bypass vulnerability in Arcserve Unified Data Protection (UDP) allows unauthenticated attackers to gain unauthorized access to protected functionality or user accounts. By manipulating specific request parameters or exploiting a logic flaw, an attacker can bypass login mechanisms without valid credentials and access administrator-level features. This vulnerability affects all UDP versions prior to 10.2. UDP 10.2 includes the necessary patches and requires no action. Versions 8.0 through 10.1 are supported and require either patch application or upgrade to 10.2. Versions 7.x and earlier are unsupported or out of maintenance and must be upgraded to 10.2 to remediate the issue.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 7.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.37%
Percentil entre todas las CVEs puntuadas: 29
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 movement75 %
Impacto principalT1078 Valid Accountsstealth · persistence · privilege escalation · initial access85 %
Impacto secundarioT1098.002 Additional Email Delegate Permissionspersistence · privilege escalation70 %

AV:A (red adyacente) y acceso a funcionalidad protegida sin credenciales válidas indica T1210. CWE-288 (autenticación débil) permite crear o secuestrar cuentas administrativas (T1078, 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

Privileged Account Management Multi-factor Authentication Disable or Remove Feature or Program Application Developer Guidance Active Directory Configuration Vulnerability Scanning

Tecnologías afectadas (1)

Arcserve — UDP

CWE

CWE-288

Referencias

https://support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions

JSON original (NVD)

Mostrar

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