Vulnerability · Published Oct 23, 2026 · Assigned by Linux

CVE-2026-99072ipv4: stop route notification sizing when nexthop group shrinks

Unrated

In plain English

A 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 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS )–Not rated
Exploit odds (30 days)0.2%top 94.7% 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: ipv4: stop route notification sizing when nexthop group shrinks Commit 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") added an RCU-only fib_nlmsg_size() call for asynchronous hardware flag notifications. fib_nlmsg_size() checks fib_info_num_path() before each iteration, then fib_info_nhc() independently reloads nh->nh_grp. If RTM_NEWNEXTHOP replaces a group with fewer paths between those loads, fib_info_nhc() returns NULL and fib_nexthop_nlmsg_size() dereferences it. Stop sizing when the indexed path is absent. Nexthop groups are dense, so the current snapshot has no later path.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linuxno fix listedDEBIAN-CVE-2026-99072
Debian:13linux6.12.113-1DEBIAN-CVE-2026-99072
Debian:14linux7.2.11-1DEBIAN-CVE-2026-99072
Ubuntu:22.04:LTSlinuxno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinuxno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinuxno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux7.3.0-10.10UBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-aws7.3.0-1004.4UBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-aws-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-aws-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-azureno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-azure-fdeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-azure-fde-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-fde-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-gcp7.3.0-1004.4UBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gcp-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gcp-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-hwe-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-ibm-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-intel-iotgno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-kvmno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidia-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidia-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-nvidia-bosno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidia-lowlatencyno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-nvidia-tegra-igxno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-oem-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-oracle7.3.0-1004.4UBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-oracle-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-oracle-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-raspi7.3.0-1004.4UBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-realtime7.3.0-10.10.1UBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-99072
Ubuntu:26.10linux-riscv7.3.0-10.10.1UBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-riscv-6.8no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-riscv-7.0no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-vmwareno fix listedUBUNTU-CVE-2026-99072
Ubuntu:24.04:LTSlinux-xilinxno fix listedUBUNTU-CVE-2026-99072
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2026-99072

Affected products (as reported)

VendorProductVersions
Linux Linux 680aea08e78c003292415518ad270bc20f9c80b1 – before 96f3fbb8575593657c7e80786dc3251d2fe3931b680aea08e78c003292415518ad270bc20f9c80b1 – before 81f0deb02a5b5477f236bbbaed1149b779a8632b680aea08e78c003292415518ad270bc20f9c80b1 – before 72d9d17092bb37b0717f12042a0817d01a1f9e78680aea08e78c003292415518ad270bc20f9c80b1 – before ad1c9f1b98c92609e9bb2ae8f05916defc3b0a54680aea08e78c003292415518ad270bc20f9c80b1 – before c1f48d1c2d5e9efd904dbbc2f2b3d41543e55c49680aea08e78c003292415518ad270bc20f9c80b1 – before ad2b3a68b8a7d5d27de88e05674e4adb1ce46d88680aea08e78c003292415518ad270bc20f9c80b1 – before d3daa33c7af92e38f2274bbd2576f58bfbaf89e6
Linux Linux 5.12

References