CVE-2021-30661

Estado: AnalizadaAlta (8.8)⚠ Explotación activa

A use after free issue was addressed with improved memory management. This issue is fixed in Safari 14.1, iOS 12.5.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

CVSS

Versión: 3.1
Vector: CVSS:3.1/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: 4.49%
Percentil entre todas las CVEs puntuadas: 91
Fecha de la puntuación: 7/10/2026

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: 3/11/2021
Plazo de remediación: 17/11/2021
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.

ExplotaciónT1203 Exploitation for Client Executionexecution90 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %

Use-after-free (CWE-416) en Safari/navegadores requiere interacción del usuario (UI:R) para procesar contenido web malicioso, permitiendo ejecución de código arbitrario. Explotación activa confirmada.

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 Privileged Account Management Limit Software Installation Execution Prevention Behavior Prevention on Endpoint Disable or Remove Feature or Program

Tecnologías afectadas (6)

Apple — Ipados Apple — Iphone OS Apple — Macos Apple — Safari Apple — Tvos Apple — Watchos

CWE

CWE-416
CWE-416

Referencias

JSON original (NVD)

Mostrar

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