CVE-2026-20809
Estado: AnalizadaAlta (7.8)—
Time-of-check time-of-use (toctou) race condition in Windows Kernel Memory allows an authorized attacker to elevate privileges locally.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.36%
- Percentil entre todas las CVEs puntuadas: 28
- 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.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation95 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 %
Vector AV:L/PR:L/UI:N indica acceso local sin interacción del usuario. TOCTOU en memoria del kernel permite escalada de privilegios, que al conseguirse habilita ejecución de código con permisos elevados.
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 (13)
Microsoft — Windows 10 1607Microsoft — Windows 10 1809Microsoft — Windows 10 21h2Microsoft — Windows 10 22h2Microsoft — Windows 11 23h2Microsoft — Windows 11 24h2Microsoft — Windows 11 25h2Microsoft — Windows Server 2012Microsoft — Windows Server 2016Microsoft — Windows Server 2019Microsoft — Windows Server 2022Microsoft — Windows Server 2022 23h2Microsoft — Windows Server 2025
CWE
- CWE-122, CWE-367
Referencias
JSON original (NVD)
Mostrar
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