CVE-2023-53821
published 2025-12-09CVE-2023-53821: In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix slab-use-after-free in decode_session6 When ipv6_vti device is set to the…
PriorityP424medium7
EPSS
0.23%
13.9th percentile
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
dump_stack_lvl+0xd9/0x150
print_address_description.constprop.0+0x2c/0x3c0
kasan_report+0x11d/0x130
decode_session6+0x103f/0x1890
__xfrm_decode_session+0x54/0xb0
vti6_tnl_xmit+0x3e6/0x1ee0
dev_hard_start_xmit+0x187/0x700
sch_direct_xmit+0x1a3/0xc30
__qdisc_run+0x510/0x17a0
__dev_queue_xmit+0x2215/0x3b10
neigh_connected_output+0x3c2/0x550
ip6_finish_output2+0x55a/0x1550
ip6_finish_output+0x6b9/0x1270
ip6_output+0x1f1/0x540
ndisc_send_skb+0xa63/0x1890
ndisc_send_rs+0x132/0x6f0
addrconf_rs_timer+0x3f1/0x870
call_timer_fn+0x1a0/0x580
expire_timers+0x29b/0x4b0
run_timer_softirq+0x326/0x910
__do_softirq+0x1d4/0x905
irq_exit_rcu+0xb7/0x120
sysvec_apic_timer_interrupt+0x97/0xc0
Allocated by task 9176:
kasan_save_stack+0x22/0x40
kasan_set_track+0x25/0x30
__kasan_slab_alloc+0x7f/0x90
kmem_cache_alloc_node+0x1cd/0x410
kmalloc_reserve+0x165/0x270
__alloc_skb+0x129/0x330
netlink_sendmsg+0x9b1/0xe30
sock_sendmsg+0xde/0x190
____sys_sendmsg+0x739/0x920
___sys_sendmsg+0x110/0x1b0
__sys_sendmsg+0xf7/0x1c0
do_syscall_64+0x39/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Freed by task 9176:
kasan_save_stack+0x22/0x40
kasan_set_track+0x25/0x30
kasan_save_free_info+0x2b/0x40
____kasan_slab_free+0x160/0x1c0
slab_free_freelist_hook+0x11b/0x220
kmem_cache_free+0xf0/0x490
skb_free_head+0x17f/0x1b0
skb_release_data+0x59c/0x850
consume_s
Affected
21 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.52-1 (bookworm) | linux 6.1.52-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < 0f0ab8d52ee0062b28367dea23c29e254a26d7db | 0f0ab8d52ee0062b28367dea23c29e254a26d7db |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < fa6c6c04f6c9b21b315023f487e5a07ae7fcf647 | fa6c6c04f6c9b21b315023f487e5a07ae7fcf647 |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < eb47e612e59c358c3968a92f90dd36c78c9a2106 | eb47e612e59c358c3968a92f90dd36c78c9a2106 |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < ec23b25e5687dbd644c0f57bcb6af22dd5a6dd36 | ec23b25e5687dbd644c0f57bcb6af22dd5a6dd36 |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < a1639a82ce14af76b6419778d343ccbff86ee626 | a1639a82ce14af76b6419778d343ccbff86ee626 |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < 55ad2309205cc00c585344374c7472420e1b2c12 | 55ad2309205cc00c585344374c7472420e1b2c12 |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < c070688bfbe7759e61e697e421b2a331b0dd74bc | c070688bfbe7759e61e697e421b2a331b0dd74bc |
| linux | linux | >= f855691975bb06373a98711e4cfe2c224244b536 < 9fd41f1ba638938c9a1195d09bc6fa3be2712f25 | 9fd41f1ba638938c9a1195d09bc6fa3be2712f25 |
| linux | linux_kernel | >= 0 < 5.10.197-1 | 5.10.197-1 |
| linux | linux_kernel | >= 0 < 6.1.52-1 | 6.1.52-1 |
| linux | linux_kernel | >= 0 < 6.4.13-1 | 6.4.13-1 |
| linux | linux_kernel | >= 0 < 6.4.13-1 | 6.4.13-1 |
| linux | linux_kernel | >= 3.19.0 < 4.14.324 | 4.14.324 |
| linux | linux_kernel | >= 4.15.0 < 4.19.293 | 4.19.293 |
| linux | linux_kernel | >= 4.20.0 < 5.4.255 | 5.4.255 |
| linux | linux_kernel | >= 5.11.0 < 5.15.128 | 5.15.128 |
| linux | linux_kernel | >= 5.16.0 < 6.1.47 | 6.1.47 |
| linux | linux_kernel | >= 5.5.0 < 5.10.192 | 5.10.192 |
| linux | linux_kernel | >= 6.2.0 < 6.4.12 | 6.4.12 |
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Red Hat
kernel: ip6_vti: fix slab-use-after-free in decode_session6
vendor_redhat·2025-12-09·CVSS 7.0
CVE-2023-53821 [MEDIUM] CWE-825 kernel: ip6_vti: fix slab-use-after-free in decode_session6
kernel: ip6_vti: fix slab-use-after-free in decode_session6
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
dump_stack_lvl+0xd9/0x150
print_address_description.constprop.0+0x2c/0x3c0
Debian
CVE-2023-53821: linux - In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fi...
vendor_debian·2023
CVE-2023-53821 CVE-2023-53821: linux - In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fi...
In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix slab-use-after-free in decode_session6 When ipv6_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ipv6_vti device sends IPv6 packets. The stack information is as follows: BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890 Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace: dump_stack_lvl+0xd9/0x150 print_address_description.constprop.0+0x2c/0x3c0 kasan_report+0x11d/0x130 decode_session6+0x103f/0x1890 __xfrm
OSV
ip6_vti: fix slab-use-after-free in decode_session6
osv·2025-12-09
CVE-2023-53821 ip6_vti: fix slab-use-after-free in decode_session6
ip6_vti: fix slab-use-after-free in decode_session6
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
dump_stack_lvl+0xd9/0x150
print_address_description.constprop.0+0x2c/0x3c0
kasa
GHSA
GHSA-j65p-q5f6-5q5p: In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set
ghsa_unreviewed·2025-12-09
CVE-2023-53821 GHSA-j65p-q5f6-5q5p: In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
dump_stack_lvl+0xd9/0x150
print_address_description.constprop.0+0x2c/0x3c0
kasan_report+0x11d/0x130
decode_session6+0x103f/0x1890
__
OSV
CVE-2023-53821: In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix slab-use-after-free in decode_session6 When ipv6_vti device is set to
osv·2025-12-09
CVE-2023-53821 CVE-2023-53821: In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix slab-use-after-free in decode_session6 When ipv6_vti device is set to
In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix slab-use-after-free in decode_session6 When ipv6_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ipv6_vti device sends IPv6 packets. The stack information is as follows: BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890 Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace: dump_stack_lvl+0xd9/0x150 print_address_description.constprop.0+0x2c/0x3c0 kasan_report+0x11d/0x130 decode_session6+0x103f/0x1890 __xfrm
No detection rules found.
No public exploits indexed.
Wiz
CVE-2023-53821 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2023-53821 CVE-2023-53821 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2023-53821 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace: dump_stack_lvl+0xd9/0x150
print_address_description.constpro
Bugzilla
CVE-2023-53821 kernel: ip6_vti: fix slab-use-after-free in decode_session6
bugzilla·2025-12-09
CVE-2023-53821 [MEDIUM] CVE-2023-53821 kernel: ip6_vti: fix slab-use-after-free in decode_session6
CVE-2023-53821 kernel: ip6_vti: fix slab-use-after-free in decode_session6
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix slab-use-after-free in decode_session6
When ipv6_vti device is set to the qdisc of the sfb type, the cb field
of the sent skb may be modified during enqueuing. Then,
slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.
The stack information is as follows:
BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890
Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
dump_stack_lvl+0xd9/0x150
print_address_description.cons
https://git.kernel.org/stable/c/0f0ab8d52ee0062b28367dea23c29e254a26d7dbhttps://git.kernel.org/stable/c/55ad2309205cc00c585344374c7472420e1b2c12https://git.kernel.org/stable/c/9fd41f1ba638938c9a1195d09bc6fa3be2712f25https://git.kernel.org/stable/c/a1639a82ce14af76b6419778d343ccbff86ee626https://git.kernel.org/stable/c/c070688bfbe7759e61e697e421b2a331b0dd74bchttps://git.kernel.org/stable/c/eb47e612e59c358c3968a92f90dd36c78c9a2106https://git.kernel.org/stable/c/ec23b25e5687dbd644c0f57bcb6af22dd5a6dd36https://git.kernel.org/stable/c/fa6c6c04f6c9b21b315023f487e5a07ae7fcf647
2025-12-09
Published