CVE-2026-64140
Gravedad CVSS v3.1:
ALTA
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
19/07/2026
Última modificación:
30/07/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
ksmbd: fix null pointer dereference in proc_show_files()<br />
<br />
When a SMB2 client opens a file with a durable v2 handle and then issues<br />
SMB2 SESSION_LOGOFF, session_fd_check() clears fp->tcon = NULL on the<br />
reconnectable file pointer but leaves the fp registered in global_ft.idr<br />
until the durable scavenger fires (up to fp->durable_timeout seconds<br />
later).<br />
<br />
During that window any read of /proc/fs/ksmbd/files (mode 0400) panics<br />
the kernel because proc_show_files() walks global_ft.idr and<br />
unconditionally dereferences fp->tcon->id with no NULL guard.<br />
<br />
Reproducer requires only a successful SMB2 SESSION_SETUP and a share<br />
configured with &#39;durable handles = yes&#39;. KASAN report on mainline<br />
70390501d194:<br />
<br />
general protection fault, probably for non-canonical address<br />
0xdffffc0000000000: 0000 [#1] SMP KASAN PTI<br />
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]<br />
RIP: 0010:proc_show_files+0x118/0x740<br />
Call Trace:<br />
proc_show_files+0x118/0x740<br />
seq_read_iter+0x4ef/0xe10<br />
proc_reg_read_iter+0x1b7/0x280<br />
...<br />
<br />
Guard the dereference. A durable-disconnected fp legitimately has no<br />
tcon; report its tree id as 0 rather than oopsing.
Impacto
Puntuación base 3.x
7.50
Gravedad 3.x
ALTA



