CVE-2021-21017

Estado: AnalizadaAlta (8.8)⚠ Explotación activa

Acrobat Reader DC versions versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by a heap-based buffer overflow vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

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: 86%
Percentil entre todas las CVEs puntuadas: 100
Fecha de la puntuación: 3/10/2026

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 Executionexecution95 %
Impacto principalT1059 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1005 Data from Local Systemcollection70 %

Buffer overflow en PDF que requiere apertura de archivo malicioso (UI:R). Permite ejecución remota de código (RCE) en contexto del usuario. CWE-787 confirma escritura fuera de límites para alcanzar ejecución arbitraria.

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 (4)

Adobe — Acrobat Adobe — Acrobat DC Adobe — Acrobat Reader Adobe — Acrobat Reader DC

CWE

CWE-122
CWE-787

Referencias

JSON original (NVD)

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