CVE-2026-31704
Estado: ModificadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: use check_add_overflow() to prevent u16 DACL size overflow
set_posix_acl_entries_dacl() and set_ntacl_dacl() accumulate ACE sizes in u16 variables. When a file has many POSIX ACL entries, the accumulated size can wrap past 65535, causing the pointer arithmetic (char *)pndace + *size to land within already-written ACEs. Subsequent writes then overwrite earlier entries, and pndacl->size gets a truncated value.
Use check_add_overflow() at each accumulation point to detect the wrap before it corrupts the buffer, consistent with existing check_mul_overflow() usage elsewhere in smbacl.c.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.16%
- Percentil entre todas las CVEs puntuadas: 5
- 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).
Tecnologías afectadas (1)
CWE
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/299f962c0b02d048fb45d248b4da493d03f3175d
- https://git.kernel.org/stable/c/41e53a773db6342ac9a689ee5ba635c31744c9f0
- https://git.kernel.org/stable/c/5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43
- https://git.kernel.org/stable/c/8d5729350b236896f51379588d9a690b7fafb8db
- https://git.kernel.org/stable/c/e1955a94b6f17f4b058afa955a6f187eb3ed7615
- https://git.kernel.org/stable/c/ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7
JSON original (NVD)
Mostrar
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: use check_add_overflow() to prevent u16 DACL size overflow\n\nset_posix_acl_entries_dacl() and set_ntacl_dacl() accumulate ACE sizes\nin u16 variables. When a file has many POSIX ACL entries, the\naccumulated size can wrap past 65535, causing the pointer arithmetic\n(char *)pndace + *size to land within already-written ACEs. Subsequent\nwrites then overwrite earlier entries, and pndacl->size gets a\ntruncated value.\n\nUse check_add_overflow() at each accumulation point to detect the\nwrap before it corrupts the buffer, consistent with existing\ncheck_mul_overflow() usage elsewhere in smbacl.c."
}
],
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