Use-after-free in Linux kernel - CVE-2026-53212
Published: June 26, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in nft_tunnel_obj_destroy() in net/netfilter/nft_tunnel.c when processing packets that still hold a reference to metadata_dst after object destruction. A local user can trigger packet queuing and object destruction to cause a denial of service.
Exploitation requires packets to remain queued, such as in a netem qdisc, until they are later dequeued.
Affected software
Ubuntu
linux (Ubuntu package)
linux-kvm (Ubuntu package)
linux-oracle-5.4 (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-azure-5.4 (Ubuntu package)
linux-fips (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-raspi (Ubuntu package)
linux-oracle (Ubuntu package)
linux-aws-5.15 (Ubuntu package)
linux-azure-fde-5.15 (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-azure-6.17 (Ubuntu package)
linux-oracle-6.17 (Ubuntu package)
linux-nvidia-6.17 (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-aws-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-53212
linux (Ubuntu package) - addressed in versions 5.4.0.234.226, 5.4.0-234.254, 5.4.0-234.254~18.04.1, 5.4.0-1066.69, 5.4.0.1080.80, 5.4.0-1080.84, 5.4.0-1108.113, 5.4.0-1108.113~18.04.1, 5.4.0.1108.137, 5.4.0.1121.117, 5.4.0-1121.128, 5.4.0.1136.133, 5.4.0-1136.146, 5.4.0-1145.158, 5.4.0-1145.158~18.04.1, 5.4.0.1145.176, 5.4.0.1160.154, 5.4.0-1160.170+fips1, 5.4.0.1162.160, 5.4.0-1162.173, 5.4.0-1162.173~18.04.1, 5.4.0.1165.167, 5.4.0-1165.174, 5.4.0-1165.174~18.04.1, 5.4.0.1167.159, 5.4.0-1167.173, 5.15.0.187.167, 5.15.0-187.197, 5.15.0.1065.65, 5.15.0-1065.67, 5.15.0-1065.67~20.04.1, 5.15.0.1076.79~20.04.1, 5.15.0-1076.80, 5.15.0.1096.95, 5.15.0-1096.104, 5.15.0.1105.101, 5.15.0-1105.107, 5.15.0.1105.109, 5.15.0-1105.110, 5.15.0.1107.104, 5.15.0.1107.111, 5.15.0-1107.111~20.04.1, 5.15.0.1108.107, 5.15.0.1108.108, 5.15.0-1108.109, 5.15.0-1108.114, 5.15.0-1108.114~20.04.1, 5.15.0-1110.116~20.04.1, 5.15.0.1112.116, 5.15.0-1112.121, 5.15.0.1113.109, 5.15.0.1113.116, 5.15.0-1113.120, 5.15.0-1113.120+fips1, 5.15.0.1118.103, 5.15.0.1118.116, 5.15.0-1118.127, 5.15.0-1118.127+fips1, 6.8.0-137.137+fips1, 6.8.0-1034.35, 6.8.0-1047.51, 6.8.0-1060.63.1, 6.8.0-1060.63~22.04.1, 6.8.0-1060.68, 6.8.0-1062.63, 6.8.0-1062.63~22.04.1, 6.8.0-1062.65, 6.8.0-1062.65+fips1, 6.8.0-1063.70, 6.8.0-1063.70~22.04.1, 6.8.0-1064.72+fips1, 6.8.0-1064.72~22.04.1, 6.8.0-1065.73, 6.8.0-1065.73+fips1, 6.8.0-1065.73~22.04.1, 6.8.1-1057.58, 6.8.1-1057.58~22.04.1, 7.0.0-29.29, 7.0.0-29.29.1, 7.0.0-1009.9, 7.0.0-1010.10, 7.0.0-1011.11, 7.0.0-1016.16
linux-kvm (Ubuntu package) - addressed in versions 5.4.0.1149.145, 5.4.0-1149.158
linux-oracle-5.4 (Ubuntu package) - update to 5.4.0-1161.171~18.04.1
linux-aws-fips (Ubuntu package) - addressed in versions 5.4.0.1163.110, 5.4.0-1163.174+fips1
linux-gcp-fips (Ubuntu package) - addressed in versions 5.4.0.1165.107, 5.4.0-1165.174+fips1
linux-azure-5.4 (Ubuntu package) - addressed in versions 5.4.0.1167.103, 5.4.0-1167.173+fips1, 5.4.0-1167.173~18.04.1
linux-fips (Ubuntu package) - addressed in versions 5.15.0.190.111, 5.15.0-190.200+fips1, 5.15.0.1110.109, 5.15.0-1110.116
linux-lowlatency (Ubuntu package) - addressed in versions 5.15.0.190.157, 5.15.0-190.200, 6.8.0-137.137.1, 6.8.0-137.137.1~22.04.1, 6.8.0-1031.32, 6.8.0-1059.62
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-190.200~20.04.1, 5.15.0.1114.104, 5.15.0.1114.111, 5.15.0-1114.124, 5.15.0-1114.124+fips1, 5.15.0-1119.128~20.04.1
linux-nvidia-tegra-igx (Ubuntu package) - addressed in versions 5.15.0-1054.54, 5.15.0.1054.56
linux-raspi (Ubuntu package) - addressed in versions 5.15.0.1108.106, 5.15.0-1108.111, 6.8.0-1062.66, 6.8.0-2051.53
linux-oracle (Ubuntu package) - addressed in versions 5.15.0.1110.106, 5.15.0-1110.116
linux-aws-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.121~20.04.1, 5.15.0-1114.124~20.04.1
linux-azure-fde-5.15 (Ubuntu package) - update to 5.15.0-1118.127~20.04.1
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-138.138~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - update to 6.8.0-1062.65~22.04.1
linux-azure-6.17 (Ubuntu package) - addressed in versions 6.17.0-42.42+1, 6.17.0-1019.22, 6.17.0-1022.22, 6.17.0-1022.25, 6.17.0-1032.32
linux-oracle-6.17 (Ubuntu package) - update to 6.17.0-1020.20
linux-nvidia-6.17 (Ubuntu package) - update to 6.17.0-1031.31
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-29.29~24.04.2
linux-gcp (Ubuntu package) - addressed in versions 7.0.0-1005.6, 7.0.0-1010.10
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1010.10
linux-aws-7.0 (Ubuntu package) - update to 7.0.0-1010.10~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16
External References
- https://git.kernel.org/stable/c/349df61526d2e39decc685d246202e3e284cfe05
- https://git.kernel.org/stable/c/55b79b1ae42372012413ce0413181d26679b17ef
- https://git.kernel.org/stable/c/5e9ee18b27fde88cb6148202b33916c66693fe82
- https://git.kernel.org/stable/c/8767fe4079affa74314d7eb3220e700150289842
- https://git.kernel.org/stable/c/941d7394efda5e054e2d6f3e0dd0f6a9ba19aaa3
- https://git.kernel.org/stable/c/c32b26aaa2f9216520a38b3f4bfeec846eb3eb8a
- https://git.kernel.org/stable/c/f9a0e4b61054cde89a2a77845293c726cc07cc43
- https://git.kernel.org/stable/c/fda6573a46ad24f35348e024905ee5bdf729797e
Related Security Bulletins
- Use-after-free in Linux kernel netfilter
- Ubuntu update for linux-azure-6.17
- Ubuntu update for linux
- Ubuntu update for linux
- Ubuntu update for linux
- Ubuntu update for linux-oem-7.0
- Ubuntu update for linux-oracle
- Ubuntu update for linux-lowlatency
- Ubuntu update for linux-nvidia-tegra-igx
- Ubuntu update for linux-azure-fde-5.15
- Ubuntu update for linux-aws-7.0
- Ubuntu update for linux-oracle-6.8
- Ubuntu update for linux-oracle-6.17
- Ubuntu update for linux-hwe-7.0
- Ubuntu update for linux-hwe-6.8
- Ubuntu update for linux-azure-5.15
- Ubuntu update for linux-gcp
- Ubuntu update for linux
- Ubuntu update for linux-nvidia-bos
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-nvidia-6.17
- Ubuntu update for linux-kvm
- Ubuntu update for linux-lowlatency
- Ubuntu update for linux-azure-5.4
- Ubuntu update for linux-raspi
- Ubuntu update for linux-gcp-fips
- Ubuntu update for linux-fips
- Ubuntu update for linux-aws-5.15
- Ubuntu update for linux-oracle-5.4
- Ubuntu update for linux-gcp-7.0
- Ubuntu update for linux-oracle-7.0
- Ubuntu update for linux-azure-7.0
- Ubuntu update for linux-raspi
- Ubuntu update for linux-aws-fips