1. Ubuntu Security Notices
  2. USN-2807-1

USN-2807-1: Linux kernel (Wily HWE) vulnerability

Publication date

10 November 2015

Overview

The system could be made to crash under certain conditions.

Releases

Packages

Details

Ben Serebrin discovered that the KVM hypervisor implementation in the Linux
kernel did not properly catch Alignment Check exceptions. An attacker in a
guest virtual machine could use this to cause a denial of service (system
crash) in the host OS.

Ben Serebrin discovered that the KVM hypervisor implementation in the Linux
kernel did not properly catch Alignment Check exceptions. An attacker in a
guest virtual machine could use this to cause a denial of service (system
crash) in the host OS.

Update instructions

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

Learn more about how to get the fixes.

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. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.

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

Ubuntu Release Package Version
14.04 trusty linux-image-4.2.0-18-generic –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-generic-lpae –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-lowlatency –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-powerpc-e500mc –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-powerpc-smp –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-powerpc64-emb –  4.2.0-18.22~14.04.1
linux-image-4.2.0-18-powerpc64-smp –  4.2.0-18.22~14.04.1

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References

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