In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: always release netdev hooks from notifier
This reverts "netfilter: nf_tables: skip netdev events generated on netns removal".
The problem is that when a veth device is released, the veth release callback will also queue the peer netns device for removal.
Its possible that the peer netns is also slated for removal. In this case, the device memory is already released before the pre_exit hook of the peer netns runs:
BUG: KASAN: slab-use-after-free in nf_hook_entry_head+0x1b8/0x1d0 Read of size 8 at addr ffff88812c0124f0 by task kworker/u8:1/45 Workqueue: netns cleanup_net Call Trace: nf_hook_entry_head+0x1b8/0x1d0 __nf_unregister_net_hook+0x76/0x510 nft_netdev_unregister_hooks+0xa0/0x220 __nft_release_hook+0x184/0x490 nf_tables_pre_exit_net+0x12f/0x1b0 ..
Order is: 1. First netns is released, veth_dellink() queues peer netns device for removal 2. peer netns is queued for removal 3. peer netns device is released, unreg event is triggered 4. unreg event is ignored because netns is going down 5. pre_exit hook calls nft_netdev_unregister_hooks but device memory might be free'd already.
CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade perfUpgrade kernel-livepatch-5.15.117-72.142Upgrade perf-debuginfoUpgrade kernelUpgrade python-perf-debuginfoUpgrade kernel-debuginfo-common-aarch64Upgrade kernel-develUpgrade kernel-toolsUpgrade kernel-headersUpgrade kernel-tools-develUpgrade bpftool-debuginfoUpgrade bpftoolUpgrade kernel-debuginfoUpgrade kernel-debuginfo-common-x86_64Upgrade kernel-tools-debuginfoUpgrade python-perf | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade kernel-toolsUpgrade python3-perf-debuginfoUpgrade kernel-debuginfo-common-aarch64Upgrade bpftoolUpgrade bpftool-debuginfoUpgrade perfUpgrade perf-debuginfoUpgrade kernel-tools-develUpgrade kernel-libbpf-staticUpgrade kernel-develUpgrade kernel-libbpfUpgrade kernel-libbpf-develUpgrade kernelUpgrade python3-perfUpgrade kernel-headersUpgrade kernel-debuginfo-common-x86_64Upgrade kernel-livepatch-6.1.34-56.100Upgrade kernel-debuginfoUpgrade kernel-tools-debuginfo | Feb 20, 2026 | Dec 30, 2025 |
| Debian | — | Upgrade linux | Dec 31, 2025 | Dec 31, 2025 |
| Redhat_linux | — | No solution exists | Jul 17, 2026 | Dec 30, 2025 |
| Ubuntu | — | Upgrade linux-azure-5.15Upgrade linux-oracle-5.15Upgrade linux-raspiUpgrade linux-nvidiaUpgrade linux-nvidia-tegra-igxUpgrade linux-gkeUpgrade linux-ibm-5.15Upgrade linuxUpgrade linux-intel-iotg-5.15Upgrade linux-hwe-5.15Upgrade linux-ibmUpgrade linux-azureUpgrade linux-gcp-5.15Upgrade linux-intel-iotgUpgrade linux-riscv-5.15Upgrade linux-lowlatencyUpgrade linux-xilinx-zynqmpUpgrade linux-oracleUpgrade linux-kvmUpgrade linux-gkeopUpgrade linux-nvidia-tegraUpgrade linux-bluefieldUpgrade linux-realtimeUpgrade linux-intel-iot-realtimeUpgrade linux-aws-5.15Upgrade linux-lowlatency-hwe-5.15Upgrade linux-gcpUpgrade linux-nvidia-tegra-5.15Upgrade linux-aws | Jan 6, 2026 | Jan 2, 2026 |
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub