=========================================================================
Ubuntu Security Notice USN-4303-2
March 17, 2020

linux-lts-xenial, linux-aws vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 14.04 ESM

Summary:

The system could be made to expose sensitive information.

Software Description:
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty

Details:

USN-4303-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04
LTS. This update provides the corresponding updates for the Linux
Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu
14.04 ESM.

Paulo Bonzini discovered that the KVM hypervisor implementation in the
Linux kernel could improperly let a nested (level 2) guest access the
resources of a parent (level 1) guest in certain situations. An attacker
could use this to expose sensitive information.

Update instructions:

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

Ubuntu 14.04 ESM:
  linux-image-4.4.0-1064-aws      4.4.0-1064.68
  linux-image-4.4.0-176-generic   4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-generic-lpae  4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-lowlatency  4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-powerpc-e500mc  4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-powerpc-smp  4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-powerpc64-emb  4.4.0-176.206~14.04.1
  linux-image-4.4.0-176-powerpc64-smp  4.4.0-176.206~14.04.1
  linux-image-aws                 4.4.0.1064.65
  linux-image-generic-lpae-lts-xenial  4.4.0.176.155
  linux-image-generic-lts-xenial  4.4.0.176.155
  linux-image-lowlatency-lts-xenial  4.4.0.176.155
  linux-image-powerpc-e500mc-lts-xenial  4.4.0.176.155
  linux-image-powerpc-smp-lts-xenial  4.4.0.176.155
  linux-image-powerpc64-emb-lts-xenial  4.4.0.176.155
  linux-image-powerpc64-smp-lts-xenial  4.4.0.176.155
  linux-image-virtual-lts-xenial  4.4.0.176.155

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:
  https://usn.ubuntu.com/4303-2
  https://usn.ubuntu.com/4303-1
  CVE-2020-2732