USN-3522-1: Linux kernel vulnerability

Ubuntu Security Notice USN-3522-1

9th January, 2018

linux, linux-aws, linux-euclid, linux-kvm vulnerability

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

  • Ubuntu 16.04 LTS


Several security issues were fixed in the Linux kernel.

Software description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-euclid - Linux kernel for Intel Euclid systems
  • linux-kvm - Linux kernel for cloud environments


Jann Horn discovered that microprocessors utilizing speculative execution
and indirect branch prediction may allow unauthorized memory reads via
sidechannel attacks. This flaw is known as Meltdown. A local attacker could
use this to expose sensitive information, including kernel memory.

Update instructions

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

Ubuntu 16.04 LTS:
linux-image-4.4.0-108-lowlatency 4.4.0-108.131
linux-image-4.4.0-108-generic 4.4.0-108.131
linux-image-4.4.0-9021-euclid 4.4.0-9021.22
linux-image-4.4.0-1047-aws 4.4.0-1047.56
linux-image-4.4.0-1015-kvm 4.4.0-1015.20

To update your system, please follow these instructions:

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.