CVE-2023-4623
Una vulnerabilidad de Use After Free en el componente net/sched: sch_hfsc (HFSC qdisc traffic control) del kernel de Linux puede ser explotada para conseguir una escalada local de privilegios. Si una clase con una curva de compartición de enlaces (es decir, con la flag HFSC_FSC establecida) tiene un padre sin una curva de compartición de enlaces, entonces init_vf() llamará a vttree_insert() en el padre, pero vttree_remove() se omitirá en update_vf(). Esto deja un puntero colgando que puede causar un Use-After-Free. Recomendamos actualizar desde el commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.
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: 0.28%
- Percentil entre todas las CVEs puntuadas: 19
- Fecha de la puntuación: 9/10/2026
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).
Tecnologías afectadas (2)
CWE
- CWE-416
- CWE-416
Referencias
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://kernel.dance/b3d26c5702c7d6c45456326e56d2ccf3f103e60f
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
JSON original (NVD)
Mostrar
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