CVE-2020-35730

Estado: AnalizadaMedia (6.1)⚠ Explotación activa

An XSS issue was discovered in Roundcube Webmail before 1.2.13, 1.3.x before 1.3.16, and 1.4.x before 1.4.10. The attacker can send a plain text e-mail message, with JavaScript in a link reference element that is mishandled by linkref_addindex in rcube_string_replacer.php.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Puntuación base: 6.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 33%
Percentil entre todas las CVEs puntuadas: 98
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).

CISA KEV — explotada activamente

Añadida al catálogo: 22/6/2023
Plazo de remediación: 13/7/2023
Uso conocido en ransomware: Unknown

🎯 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 principalT1059.007 JavaScriptexecution75 %

XSS en Roundcube via email con JavaScript malicioso. AV:N, UI:R (requiere interacción del usuario al abrir email) → T1189 drive-by. Impacto: ejecución de JavaScript en contexto del navegador; potencial acceso a sesiones/credenciales.

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 Content User Training Execution Prevention Behavior Prevention on Endpoint Disable or Remove Feature or Program Application Isolation and Sandboxing

Tecnologías afectadas (3)

Debian — Debian Linux Fedoraproject — Fedora Roundcube — Webmail

CWE

CWE-79
CWE-79

Referencias

JSON original (NVD)

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    },
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      "value": "Se detectó un problema de XSS en Roundcube Webmail en versiones anteriores a la 1.2.13, 1.3.x en versiones anteriores a la 1.3.16 y 1.4.x en versiones anteriores a la 1.4.10. El atacante puede enviar un mensaje de correo electrónico de texto sin formato, con JavaScript en un elemento de referencia de enlace que es manejado inapropiadamente por linkref_addindex en rcube_string_replacer.php."
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