CVE-2026-23003

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-23003
In the Linux kernel, the following vulnerability has been resolved: ip6_tunnel: use skb_vlan_inet_prepare() in __ip6_tnl_rcv() Blamed commit did not take care of VLAN encapsulations as spotted by syzbot [1]. Use skb_vlan_inet_prepare() instead of pskb_inet_may_pull(). [1] BUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline] BUG: KMSAN: uninit-value in INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline] BUG: KMSAN: uninit-value in IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321 __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline] INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline] IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321 ip6ip6_dscp_ecn_decapsulate+0x16f/0x1b0 net/ipv6/ip6_tunnel.c:729 __ip6_tnl_rcv+0xed9/0x1b50 net/ipv6/ip6_tunnel.c:860 ip6_tnl_rcv+0xc3/0x100 net/ipv6/ip6_tunnel.c:903 gre_rcv+0x1529/0x1b90 net/ipv6/ip6_gre.c:-1 ip6_protocol_deliver_rcu+0x1c89/0x2c60 net/ipv6/ip6_input.c:438 ip6_input_finish+0x1f4/0x4a0 net/ipv6/ip6_input.c:489 NF_HOOK include/linux/netfilter.h:318 [inline] ip6_input+0x9c/0x330 net/ipv6/ip6_input.c:500 ip6_mc_input+0x7ca/0xc10 net/ipv6/ip6_input.c:590 dst_input include/net/dst.h:474 [inline] ip6_rcv_finish+0x958/0x990 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:318 [inline] ipv6_rcv+0xf1/0x3c0 net/ipv6/ip6_input.c:311 __netif_receive_skb_one_core net/core/dev.c:6139 [inline] __netif_receive_skb+0x1df/0xac0 net/core/dev.c:6252 netif_receive_skb_internal net/core/dev.c:6338 [inline] netif_receive_skb+0x57/0x630 net/core/dev.c:6397 tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485 tun_get_user+0x5c0e/0x6c60 drivers/net/tun.c:1953 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [inline] vfs_write+0xbe2/0x15d0 fs/read_write.c:686 ksys_write fs/read_write.c:738 [inline] __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4960 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6712 sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2995 tun_alloc_skb drivers/net/tun.c:1461 [inline] tun_get_user+0x1142/0x6c60 drivers/net/tun.c:1794 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [inline] vfs_write+0xbe2/0x15d0 fs/read_write.c:686 ksys_write fs/read_write.c:738 [inline] __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 UID: 0 PID: 6465 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025

7.5 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/2f03dafea0a8096a2eb60f551218b360e5bab9a3 Patch
https://git.kernel.org/stable/c/64c71d60a21a9ed0a802483dcd422b5b24eb1abe Patch
https://git.kernel.org/stable/c/81c734dae203757fb3c9eee6f9896386940776bd Patch
https://git.kernel.org/stable/c/9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af Patch
https://git.kernel.org/stable/c/b9f915340f25cae1562f18e1eb52deafca328414 Patch
https://git.kernel.org/stable/c/df5ffde9669314500809bc498ae73d6d3d9519ac Patch
https://git.kernel.org/stable/c/f9c5c5b791d3850570796f9e067629474e613796 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*
History

27 Apr 2026, 14:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : 5.5 		v2 : unknown
v3 : 7.5

25 Mar 2026, 19:22

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:-:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
First Time Linux
Linux linux Kernel
CWE CWE-908
Summary
  • (es) En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: ip6_tunnel: usar skb_vlan_inet_prepare() en __ip6_tnl_rcv() El commit culpable no tuvo en cuenta las encapsulaciones VLAN como fue detectado por syzbot [1]. Usar skb_vlan_inet_prepare() en lugar de pskb_inet_may_pull(). [1] ERROR: KMSAN: valor no inicializado en __INET_ECN_decapsulate include/net/inet_ecn.h:253 [en línea] ERROR: KMSAN: valor no inicializado en INET_ECN_decapsulate include/net/inet_ecn.h:275 [en línea] ERROR: KMSAN: valor no inicializado en IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321 __INET_ECN_decapsulate include/net/inet_ecn.h:253 [en línea] INET_ECN_decapsulate include/net/inet_ecn.h:275 [en línea] IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321 ip6ip6_dscp_ecn_decapsulate+0x16f/0x1b0 net/ipv6/ip6_tunnel.c:729 __ip6_tnl_rcv+0xed9/0x1b50 net/ipv6/ip6_tunnel.c:860 ip6_tnl_rcv+0xc3/0x100 net/ipv6/ip6_tunnel.c:903 gre_rcv+0x1529/0x1b90 net/ipv6/ip6_gre.c:-1 ip6_protocol_deliver_rcu+0x1c89/0x2c60 net/ipv6/ip6_input.c:438 ip6_input_finish+0x1f4/0x4a0 net/ipv6/ip6_input.c:489 NF_HOOK include/linux/netfilter.h:318 [en línea] ip6_input+0x9c/0x330 net/ipv6/ip6_input.c:500 ip6_mc_input+0x7ca/0xc10 net/ipv6/ip6_input.c:590 dst_input include/net/dst.h:474 [en línea] ip6_rcv_finish+0x958/0x990 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:318 [en línea] ipv6_rcv+0xf1/0x3c0 net/ipv6/ip6_input.c:311 __netif_receive_skb_one_core net/core/dev.c:6139 [en línea] __netif_receive_skb+0x1df/0xac0 net/core/dev.c:6252 netif_receive_skb_internal net/core/dev.c:6338 [en línea] netif_receive_skb+0x57/0x630 net/core/dev.c:6397 tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485 tun_get_user+0x5c0e/0x6c60 drivers/net/tun.c:1953 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [en línea] vfs_write+0xbe2/0x15d0 fs/read_write.c:686 ksys_write fs/read_write.c:738 [en línea] __do_sys_write fs/read_write.c:749 [en línea] __se_sys_write fs/read_write.c:746 [en línea] __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [en línea] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f El valor no inicializado fue creado en: slab_post_alloc_hook mm/slub.c:4960 [en línea] slab_alloc_node mm/slub.c:5263 [en línea] kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690 alloc_skb include/linux/skbuff.h:1383 [en línea] alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6712 sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2995 tun_alloc_skb drivers/net/tun.c:1461 [en línea] tun_get_user+0x1142/0x6c60 drivers/net/tun.c:1794 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [en línea] vfs_write+0xbe2/0x15d0 fs/read_write.c:686 ksys_write fs/read_write.c:738 [en línea] __do_sys_write fs/read_write.c:749 [en línea] __se_sys_write fs/read_write.c:746 [en línea] __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746 x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [en línea] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 UID: 0 PID: 6465 Comm: syz.0.17 No contaminado syzkaller #0 PREEMPT(none) Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 25/10/2025
References () https://git.kernel.org/stable/c/2f03dafea0a8096a2eb60f551218b360e5bab9a3 - () https://git.kernel.org/stable/c/2f03dafea0a8096a2eb60f551218b360e5bab9a3 - Patch
References () https://git.kernel.org/stable/c/64c71d60a21a9ed0a802483dcd422b5b24eb1abe - () https://git.kernel.org/stable/c/64c71d60a21a9ed0a802483dcd422b5b24eb1abe - Patch
References () https://git.kernel.org/stable/c/81c734dae203757fb3c9eee6f9896386940776bd - () https://git.kernel.org/stable/c/81c734dae203757fb3c9eee6f9896386940776bd - Patch
References () https://git.kernel.org/stable/c/9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af - () https://git.kernel.org/stable/c/9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af - Patch
References () https://git.kernel.org/stable/c/b9f915340f25cae1562f18e1eb52deafca328414 - () https://git.kernel.org/stable/c/b9f915340f25cae1562f18e1eb52deafca328414 - Patch
References () https://git.kernel.org/stable/c/df5ffde9669314500809bc498ae73d6d3d9519ac - () https://git.kernel.org/stable/c/df5ffde9669314500809bc498ae73d6d3d9519ac - Patch
References () https://git.kernel.org/stable/c/f9c5c5b791d3850570796f9e067629474e613796 - () https://git.kernel.org/stable/c/f9c5c5b791d3850570796f9e067629474e613796 - Patch

06 Feb 2026, 17:16

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/64c71d60a21a9ed0a802483dcd422b5b24eb1abe -
  • () https://git.kernel.org/stable/c/9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af -
  • () https://git.kernel.org/stable/c/f9c5c5b791d3850570796f9e067629474e613796 -

30 Jan 2026, 10:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/2f03dafea0a8096a2eb60f551218b360e5bab9a3 -

25 Jan 2026, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2026-01-25 15:15

Updated : 2026-04-27 14:16

NVD link : CVE-2026-23003

Mitre link : CVE-2026-23003

CVE.ORG link : CVE-2026-23003

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-908

Use of Uninitialized Resource