USN-3819-1: Linux kernel vulnerability

14 November 2018

linux, linux-aws, linux-gcp, linux-kvm, linux-raspi2 vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 18.10

Summary

The system could be made to crash or run programs as an administrator.

Software Description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2

Details

Felix Wilhelm discovered that the Xen netback driver in the Linux kernel did not properly perform input validation in some situations. An attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.10
linux-image-4.18.0-1003-gcp - 4.18.0-1003.4
linux-image-4.18.0-1004-aws - 4.18.0-1004.5
linux-image-4.18.0-1004-kvm - 4.18.0-1004.4
linux-image-4.18.0-1006-raspi2 - 4.18.0-1006.8
linux-image-4.18.0-11-generic - 4.18.0-11.12
linux-image-4.18.0-11-generic-lpae - 4.18.0-11.12
linux-image-4.18.0-11-lowlatency - 4.18.0-11.12
linux-image-4.18.0-11-snapdragon - 4.18.0-11.12
linux-image-aws - 4.18.0.1004.4
linux-image-gcp - 4.18.0.1003.3
linux-image-generic - 4.18.0.11.12
linux-image-generic-lpae - 4.18.0.11.12
linux-image-gke - 4.18.0.1003.3
linux-image-kvm - 4.18.0.1004.4
linux-image-lowlatency - 4.18.0.11.12
linux-image-raspi2 - 4.18.0.1006.3
linux-image-snapdragon - 4.18.0.11.12

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to reboot your computer to make all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.

References