Vulnerability · Published May 8, 2026 · Assigned by Linux

CVE-2026-43451netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path

Medium 5.5

In plain English

A medium-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)5.5Medium
Exploit odds (30 days)0.1%top 98.0% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path nfqnl_recv_verdict() calls find_dequeue_entry() to remove the queue entry from the queue data structures, taking ownership of the entry. For PF_BRIDGE packets, it then calls nfqa_parse_bridge() to parse VLAN attributes. If nfqa_parse_bridge() returns an error (e.g. NFQA_VLAN present but NFQA_VLAN_TCI missing), the function returns immediately without freeing the dequeued entry or its sk_buff. This leaks the nf_queue_entry, its associated sk_buff, and all held references (net_device refcounts, struct net refcount). Repeated triggering exhausts kernel memory. Fix this by dropping the entry via nfqnl_reinject() with NF_DROP verdict on the error path, consistent with other error handling in this file.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.170-1DEBIAN-CVE-2026-43451
Debian:13linux6.12.85-1DEBIAN-CVE-2026-43451
Debian:14linux6.19.10-1DEBIAN-CVE-2026-43451
Ubuntu:22.04:LTSlinux5.15.0-186.196UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux6.8.0-136.136UBUNTU-CVE-2026-43451
Ubuntu:25.10linuxno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-aws5.15.0-1112.119UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-aws6.8.0-1061.64UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-awsno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1061.64~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure5.15.0-1117.126UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure6.8.0-1063.71UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-azureno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1063.71~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-fde5.15.0-1117.126UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-fde6.8.0-1062.69UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-azure-fdeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-azure-fde-6.86.8.0-1062.69~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gcp5.15.0-1112.122UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gcp6.8.0-1064.72UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-gcpno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1064.72~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gke5.15.0-1108.114UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gke6.8.0-1059.67UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-gkeop5.15.0-1095.103UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1046.50UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-hwe-6.86.8.0-136.136~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-ibm5.15.0-1106.110UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-ibm6.8.0-1061.62UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1061.62~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-intel-iotg5.15.0-1107.113UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-kvm5.15.0-1104.109UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-lowlatency5.15.0-184.194UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-136.136.2UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-136.136.2~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia5.15.0-1107.108UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1059.62UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1059.62~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1059.62.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia-tegra5.15.0-1064.66UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1030.31UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-nvidia-tegra-igx5.15.0-1053.53UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oracle5.15.0-1109.115UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oracle6.8.0-1058.61UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-oracleno fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1058.61~22.04.1UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-raspi5.15.0-1106.109UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-raspi6.8.0-1061.65UBUNTU-CVE-2026-43451
Ubuntu:25.10linux-raspino fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:25.10linux-realtimeno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-43451
Ubuntu:25.10linux-riscvno fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-136.136~22.04.3UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-vmware6.8.0-1008.8UBUNTU-CVE-2026-43451
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1033.34UBUNTU-CVE-2026-43451
Ubuntu:22.04:LTSlinux-xilinx-zynqmp5.15.0-1075.79UBUNTU-CVE-2026-43451

Affected products (as reported)

VendorProductVersions
Linux Linux 8d45ff22f1b43249f0cf1baafe0262ca10d1666e – before a907bea273b60d3e604ec4e8e1f6c499548057948d45ff22f1b43249f0cf1baafe0262ca10d1666e – before 0b18d1b834ab5a5009be70b530f978d7989e445b8d45ff22f1b43249f0cf1baafe0262ca10d1666e – before b38d2b4603fd3dda24eb8b3dd81c18a0930be97b8d45ff22f1b43249f0cf1baafe0262ca10d1666e – before 47b1c5d1b0944aa88299f55a846fabaefc7569828d45ff22f1b43249f0cf1baafe0262ca10d1666e – before cf4a4df38d1747e06fc54f9879bd7a6f4178032f8d45ff22f1b43249f0cf1baafe0262ca10d1666e – before 9853d94b82d303fc4ac37d592a23a154096ecd418d45ff22f1b43249f0cf1baafe0262ca10d1666e – before 208669df703a25a601f45822b10c413f258bf2758d45ff22f1b43249f0cf1baafe0262ca10d1666e – before f1ba83755d81c6fc66ac7acd723d238f974091e9
Linux Linux 4.7

References