CVE-2026-53271
Estado: AnalizadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers
smb2_oplock_break_noti() and smb2_lease_break_noti() read opinfo->conn into a local with neither READ_ONCE() nor a NULL check. Both run from oplock_break() after opinfo_get_list() has dropped ci->m_lock, so a concurrent SMB2 LOGOFF (session_fd_check()) can set op->conn = NULL under ci->m_lock within that window. ksmbd_conn_r_count_inc(conn) then writes through NULL at offset 0xc4 -- a remotely triggerable oops.
Guard both reads the way compare_guid_key() already does: read opinfo->conn with READ_ONCE() and return early if it is NULL, before allocating the work struct so nothing leaks.
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A NULL conn means the client is gone and the break is moot, so return 0; oplock_break() treats that as success and runs the normal teardown.
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: 0.11%
- Percentil entre todas las CVEs puntuadas: 1
- Fecha de la puntuación: 2/10/2026
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
- CWE-476
Referencias
- https://git.kernel.org/stable/c/1ff58dcfcab434ebb51649da33774fbb8e1f7b67
- https://git.kernel.org/stable/c/75e33deda658c1ab3a9336cbdb1436536f9b3660
- https://git.kernel.org/stable/c/945a86b21b40fb17183f5b27461baa6f03e2467f
- https://git.kernel.org/stable/c/b003086d76968298f22e7cf62239833b5a3a06b1
- https://git.kernel.org/stable/c/e735dbd489e3ea02be78dba991056fe1138be51e
JSON original (NVD)
Mostrar
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