=========================================================================
Ubuntu Security Notice USN-3848-2
December 20, 2018

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

- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

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-3848-1 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 LTS.

It was discovered that a double free existed in the AMD GPIO driver in the
Linux kernel. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2017-18174)

It was discovered that an integer overrun vulnerability existed in the
POSIX timers implementation in the Linux kernel. A local attacker could use
this to cause a denial of service. (CVE-2018-12896)

Kanda Motohiro discovered that writing extended attributes to an XFS file
system in the Linux kernel in certain situations could cause an error
condition to occur. A local attacker could use this to cause a denial of
service. (CVE-2018-18690)

It was discovered that an integer overflow vulnerability existed in the
CDROM driver of the Linux kernel. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2018-18710)

Update instructions:

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

Ubuntu 14.04 LTS:
  linux-image-4.4.0-1037-aws      4.4.0-1037.40
  linux-image-4.4.0-141-generic   4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-generic-lpae  4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-lowlatency  4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-powerpc-e500mc  4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-powerpc-smp  4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-powerpc64-emb  4.4.0-141.167~14.04.1
  linux-image-4.4.0-141-powerpc64-smp  4.4.0-141.167~14.04.1
  linux-image-aws                 4.4.0.1037.37
  linux-image-generic-lpae-lts-xenial  4.4.0.141.121
  linux-image-generic-lts-xenial  4.4.0.141.121
  linux-image-lowlatency-lts-xenial  4.4.0.141.121
  linux-image-powerpc-e500mc-lts-xenial  4.4.0.141.121
  linux-image-powerpc-smp-lts-xenial  4.4.0.141.121
  linux-image-powerpc64-emb-lts-xenial  4.4.0.141.121
  linux-image-powerpc64-smp-lts-xenial  4.4.0.141.121

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/usn/usn-3848-2
  https://usn.ubuntu.com/usn/usn-3848-1
  CVE-2017-18174, CVE-2018-12896, CVE-2018-18690, CVE-2018-18710

Package Information:
  https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1037.40
  https://launchpad.net/ubuntu/+source/linux-lts-xenial/4.4.0-141.167~14.04.1