CVE-2021-21193
Un uso de la memoria previamente liberada en Blink en Google Chrome versiones anteriores a 89.0.4389.90, permitía a un atacante remoto explotar la corrupción de la pila por medio de una página HTML diseñada
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: 9.87%
- Percentil entre todas las CVEs puntuadas: 95
- Fecha de la puntuación: 8/10/2026
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
💥 Exploits públicos
Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.
- Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub
⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1059.007JavaScriptexecution75 %
Vulnerabilidad de use-after-free en navegador Chrome requiere HTML malicioso y interacción del usuario (UI:R). Permite corrupción de heap → ejecución de código (T1059). Vector CVSS AV:N/AC:L/PR:N/UI:R confirma T1203. Ransomware sugiere impacto de DOS como objetivo secundario.
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
Tecnologías afectadas (3)
CWE
- CWE-416
- CWE-416
Referencias
- https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop_12.html
- https://crbug.com/1186287
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N52OWF4BAP3JNK2QYGU3Q6QUVDZDCIMQ/
- https://security.gentoo.org/glsa/202104-08
- https://www.debian.org/security/2021/dsa-4886
- https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop_12.html
- https://crbug.com/1186287
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N52OWF4BAP3JNK2QYGU3Q6QUVDZDCIMQ/
- https://security.gentoo.org/glsa/202104-08
- https://www.debian.org/security/2021/dsa-4886
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21193
JSON original (NVD)
Mostrar
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