CVE-2026-20934
Estado: AnalizadaAlta (7.5)—
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows SMB Server allows an authorized attacker to elevate privileges over a network.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.76%
- Percentil entre todas las CVEs puntuadas: 54
- 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
T1210Exploitation of Remote Serviceslateral movement85 % - Impacto principal
T1068Exploitation for Privilege Escalationprivilege escalation90 %
Race condition en SMB Server (CWE-362) exploitable remotamente por usuario autenticado (PR:L) sin interacción. Permite escalada de privilegios sobre red, típica de T1210 con impacto T1068.
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-362
Referencias
JSON original (NVD)
Mostrar
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