USN-3249-1: Linux kernel vulnerability

29 March 2017

linux, linux-aws, linux-gke, linux-raspi2, linux-snapdragon vulnerability

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

  • Ubuntu 16.04 LTS

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-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon Processors

Details

It was discovered that the xfrm framework for transforming packets in the Linux kernel did not properly validate data received from user space. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code with administrative privileges.

Update instructions

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

Ubuntu 16.04 LTS
linux-image-4.4.0-1009-gke - 4.4.0-1009.9
linux-image-4.4.0-1012-aws - 4.4.0-1012.21
linux-image-4.4.0-1051-raspi2 - 4.4.0-1051.58
linux-image-4.4.0-1054-snapdragon - 4.4.0-1054.58
linux-image-4.4.0-71-generic - 4.4.0-71.92
linux-image-4.4.0-71-generic-lpae - 4.4.0-71.92
linux-image-4.4.0-71-lowlatency - 4.4.0-71.92
linux-image-4.4.0-71-powerpc-e500mc - 4.4.0-71.92
linux-image-4.4.0-71-powerpc-smp - 4.4.0-71.92
linux-image-4.4.0-71-powerpc64-smp - 4.4.0-71.92
linux-image-aws - 4.4.0.1012.15
linux-image-generic - 4.4.0.71.77
linux-image-generic-lpae - 4.4.0.71.77
linux-image-gke - 4.4.0.1009.11
linux-image-lowlatency - 4.4.0.71.77
linux-image-powerpc-e500mc - 4.4.0.71.77
linux-image-powerpc-smp - 4.4.0.71.77
linux-image-powerpc64-smp - 4.4.0.71.77
linux-image-raspi2 - 4.4.0.1051.52
linux-image-snapdragon - 4.4.0.1054.47

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