CVE-2026-64554
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
27/07/2026
Última modificación:
27/07/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()<br />
<br />
br_ip6_fragment() gets prevhdr, a pointer into the skb head, from<br />
ip6_find_1stfragopt(), then calls skb_checksum_help(). For a cloned skb<br />
skb_checksum_help() reallocates the head via pskb_expand_head(), leaving<br />
prevhdr dangling. It is later dereferenced in ip6_frag_next(), causing a<br />
use-after-free write.<br />
<br />
Save prevhdr&#39;s offset before skb_checksum_help() and recompute it after,<br />
like commit ef0efcd3bd3f ("ipv6: Fix dangling pointer when ipv6<br />
fragment").<br />
<br />
BUG: KASAN: slab-use-after-free in ip6_frag_next (net/ipv6/ip6_output.c:857)<br />
Write of size 1 at addr ffff888013ff5016 by task exploit/141<br />
Call Trace:<br />
...<br />
kasan_report (mm/kasan/report.c:595)<br />
ip6_frag_next (net/ipv6/ip6_output.c:857)<br />
br_ip6_fragment (net/ipv6/netfilter.c:212)<br />
nf_ct_bridge_post (net/bridge/netfilter/nf_conntrack_bridge.c:407)<br />
nf_hook_slow (net/netfilter/core.c:619)<br />
br_forward_finish (net/bridge/br_forward.c:66)<br />
__br_forward (net/bridge/br_forward.c:115)<br />
maybe_deliver (net/bridge/br_forward.c:191)<br />
br_flood (net/bridge/br_forward.c:245)<br />
br_handle_frame_finish (net/bridge/br_input.c:229)<br />
br_handle_frame (net/bridge/br_input.c:442)<br />
...<br />
packet_sendmsg (net/packet/af_packet.c:3114)<br />
...<br />
do_syscall_64 (arch/x86/entry/syscall_64.c:94)<br />
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)<br />
Kernel panic - not syncing: Fatal exception in interrupt
Impacto
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/00c06ef8c018493943891a7d0ca82b71b24f3180
- https://git.kernel.org/stable/c/1c4f67c89fd27c4df4c70b135c2c59627698b3c0
- https://git.kernel.org/stable/c/2731efa6364e47934c96eb69e01ea131e8af8030
- https://git.kernel.org/stable/c/4ac981a8b7ce7aec99a52d08f8a8953e8e120067
- https://git.kernel.org/stable/c/86f3ce81dd2b4b0aa2c3016c989a943e4b1b643d
- https://git.kernel.org/stable/c/8c10778ec674b67a07ea042fcba64270f3f38a5a
- https://git.kernel.org/stable/c/c141f69d0a0fb16964dbc293650047e69bda8af7
- https://git.kernel.org/stable/c/f2e6596d10783557aeb9668da2a3b4d19deb2001



