CVE-2026-43450
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
08/05/2026
Última modificación:
12/05/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table()<br />
<br />
nfnl_cthelper_dump_table() has a &#39;goto restart&#39; that jumps to a label<br />
inside the for loop body. When the "last" helper saved in cb->args[1]<br />
is deleted between dump rounds, every entry fails the (cur != last)<br />
check, so cb->args[1] is never cleared. The for loop finishes with<br />
cb->args[0] == nf_ct_helper_hsize, and the &#39;goto restart&#39; jumps back<br />
into the loop body bypassing the bounds check, causing an 8-byte<br />
out-of-bounds read on nf_ct_helper_hash[nf_ct_helper_hsize].<br />
<br />
The &#39;goto restart&#39; block was meant to re-traverse the current bucket<br />
when "last" is no longer found, but it was placed after the for loop<br />
instead of inside it. Move the block into the for loop body so that<br />
the restart only occurs while cb->args[0] is still within bounds.<br />
<br />
BUG: KASAN: slab-out-of-bounds in nfnl_cthelper_dump_table+0x9f/0x1b0<br />
Read of size 8 at addr ffff888104ca3000 by task poc_cthelper/131<br />
Call Trace:<br />
nfnl_cthelper_dump_table+0x9f/0x1b0<br />
netlink_dump+0x333/0x880<br />
netlink_recvmsg+0x3e2/0x4b0<br />
sock_recvmsg+0xde/0xf0<br />
__sys_recvfrom+0x150/0x200<br />
__x64_sys_recvfrom+0x76/0x90<br />
do_syscall_64+0xc3/0x6e0<br />
<br />
Allocated by task 1:<br />
__kvmalloc_node_noprof+0x21b/0x700<br />
nf_ct_alloc_hashtable+0x65/0xd0<br />
nf_conntrack_helper_init+0x21/0x60<br />
nf_conntrack_init_start+0x18d/0x300<br />
nf_conntrack_standalone_init+0x12/0xc0
Impacto
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/05018cd9370f77bb18fbf6e15ff33c7a06f10b3c
- https://git.kernel.org/stable/c/0605e1985a95d4334a67869aee45a47e82301abf
- https://git.kernel.org/stable/c/3cc328ffc32ddb389cba7b78b6aa95d995c2876e
- https://git.kernel.org/stable/c/4a1f6ee69267a5f524102c028981410eeacfa3da
- https://git.kernel.org/stable/c/61b3a1f8621df1a5928118313f133996f6a786db
- https://git.kernel.org/stable/c/6dcee8496d53165b2d8a5909b3050b62ae71fe89
- https://git.kernel.org/stable/c/894c5780ddadd5fde0e16f66587918e6be1504c4
- https://git.kernel.org/stable/c/92441f6d9405a0c18d03f278b395e782f79a4a30



