cbcvebase.
CVE-2026-23003
published 2026-01-25

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…

PriorityP423medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.47%
38.0th percentile
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:74

Affected

83 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
debianlinux-6.1< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 350a6640fac4b53564ec20aa3f4a0922cb0ba5e6 < 2f03dafea0a8096a2eb60f551218b360e5bab9a32f03dafea0a8096a2eb60f551218b360e5bab9a3
linuxlinux>= 5.10.210 < 5.10.2495.10.249
linuxlinux>= 5.15.149 < 5.15.1995.15.199
linuxlinux>= 6.1.77 < 6.1.1626.1.162
linuxlinux>= 6.6.16 < 6.6.1226.6.122
linuxlinux>= 6.7.4 < 6.86.8
linuxlinux>= 8d975c15c0cd744000ca386247432d57b21f9df0 < df5ffde9669314500809bc498ae73d6d3d9519acdf5ffde9669314500809bc498ae73d6d3d9519ac
linuxlinux>= 8d975c15c0cd744000ca386247432d57b21f9df0 < b9f915340f25cae1562f18e1eb52deafca328414b9f915340f25cae1562f18e1eb52deafca328414
linuxlinux>= 8d975c15c0cd744000ca386247432d57b21f9df0 < 81c734dae203757fb3c9eee6f9896386940776bd81c734dae203757fb3c9eee6f9896386940776bd
linuxlinux>= a9bc32879a08f23cdb80a48c738017e39aea1080 < f9c5c5b791d3850570796f9e067629474e613796f9c5c5b791d3850570796f9e067629474e613796
linuxlinux>= af6b5c50d47ab43e5272ad61935d0ed2e264d3f0 < 64c71d60a21a9ed0a802483dcd422b5b24eb1abe64c71d60a21a9ed0a802483dcd422b5b24eb1abe
linuxlinux>= d54e4da98bbfa8c257bdca94c49652d81d18a4d8 < 9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af9e1c8c2a33d0a7b1f637b5d0602fe56ed10166af
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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