=========================================================================
Ubuntu Security Notice USN-4096-1
August 13, 2019

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

- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

The system could be made to expose sensitive information.

Software Description:
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-aws-hwe: Linux kernel for Amazon Web Services (AWS-HWE) systems

Details:

Andrei Vlad Lutas and Dan Lutas discovered that some x86 processors
incorrectly handle SWAPGS instructions during speculative execution. A
local attacker could use this to expose sensitive information (kernel
memory).

Update instructions:

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

Ubuntu 19.04:
  linux-image-5.0.0-1012-aws      5.0.0-1012.13
  linux-image-aws                 5.0.0.1012.12

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1045-aws     4.15.0-1045.47
  linux-image-aws                 4.15.0.1045.44

Ubuntu 16.04 LTS:
  linux-image-4.15.0-1045-aws     4.15.0-1045.47~16.04.1
  linux-image-aws-hwe             4.15.0.1045.45

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/4096-1
  CVE-2019-1125

Package Information:
  https://launchpad.net/ubuntu/+source/linux-aws/5.0.0-1012.13
  https://launchpad.net/ubuntu/+source/linux-aws/4.15.0-1045.47
  https://launchpad.net/ubuntu/+source/linux-aws-hwe/4.15.0-1045.47~16.04.1