USN-8875-1: Multiple Linux Kernel Flaws, ABI Bump and Mandatory Reboot

On 6 October 2026, Ubuntu published security advisory USN-8875-1, which fixes several vulnerabilities in the Linux kernel for the 22.04 LTS (jammy) and 20.04 LTS releases. The advisory concerns anyone managing servers, VPS or cloud instances on these versions: the packages affected are not just the generic linux kernel, but also the variants specific to cloud providers.

What the advisory fixes

Among the listed flaws, Ubuntu provides detail on CVE-2022-3114: the i.MX clock driver failed to properly handle certain memory allocation failure conditions, causing a null pointer dereference. A local attacker can exploit this to trigger a denial of service, i.e. a system crash.

The advisory then lists, in more general terms, further fixes spread across a very wide range of kernel subsystems: from the block layer to cryptography, from filesystems such as Btrfs, XFS, NFS and exFAT through to networking (netfilter, IPv6, SCTP, Bluetooth), io_uring, KVM and USB drivers. Ubuntu's official text does not provide a complete list of CVEs for these additional fixes, merely indicating which subsystems are affected.

Packages affected

The kernels affected include, among others: linux, linux-aws, linux-aws-5.15, linux-aws-fips, linux-azure, linux-azure-5.15, linux-azure-fde-5.15, linux-azure-fips, linux-fips, linux-gke, linux-gkeop, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, linux-intel-iot-realtime, linux-intel-iotg, linux-kvm, linux-lowlatency, linux-oracle, linux-realtime and linux-xilinx-zynqmp. Anyone running AWS, Azure, GKE or Oracle Cloud instances on Ubuntu 22.04/20.04 needs to check which kernel variant they're using.

Update and ABI bump

Ubuntu flags an operational point that shouldn't be overlooked: the update involves an ABI change, meaning the kernel gets a new version number. This requires recompiling and reinstalling all third-party kernel modules installed on the system. If the standard metapackages (linux-generic, linux-generic-lts-RELEASE, linux-virtual) haven't been manually removed, the standard system upgrade handles this automatically.

After updating via the usual system commands (apt update && apt upgrade), you need to reboot the machine for the changes to take effect. For those using realtime kernels (linux-realtime, linux-intel-iot-realtime), availability requires an Ubuntu Pro subscription.

Full details of the affected packages and fixed versions are published in the official advisory at ubuntu.com/security/notices/USN-8875-1.