CVE-2021-47961

Estado: AnalizadaAlta (8.1)—

A plaintext storage of a password vulnerability in Synology SSL VPN Client before 1.4.5-0684 allows remote attackers to access or influence the user's PIN code due to insecure storage. This may lead to unauthorized VPN configuration and potential interception of subsequent VPN traffic when combined with user interaction.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Puntuación base: 8.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.32%
Percentil entre todas las CVEs puntuadas: 23
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.

ExplotaciónT1203 Exploitation for Client Executionexecution85 %
Impacto principalT1212 Exploitation for Credential Accesscredential access90 %
Impacto secundarioT1078 Valid Accountsstealth · persistence · privilege escalation · initial access75 %

UI:R (interacción del usuario) → T1203. Almacenamiento en texto plano de credenciales (CWE-256) → obtención de PIN/credenciales (T1212) y acceso no autorizado (T1078).

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

Application Developer Guidance Application Isolation and Sandboxing Exploit Protection Update Software Active Directory Configuration User Training

Tecnologías afectadas (1)

Synology — SSL VPN Client

CWE

CWE-256

Referencias

https://www.synology.com/en-global/security/advisory/Synology_SA_26_05

JSON original (NVD)

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