Ubuntu 16.04 LTS USN-3848-1: Critical Kernel Denial of Service Issues

ubuntu

December 20, 2018

Several security issues were fixed in the Linux kernel.

Summary

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-kvm: Linux kernel for cloud environments

- linux-raspi2: Linux kernel for Raspberry Pi 2

- linux-snapdragon: Linux kernel for Snapdragon processors

Details:

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...

Read the Full Advisory

Topics Covered

security advisory denial of service DoS Ubuntu kernel XFS filesystem AMD GPIO

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1039-kvm      4.4.0-1039.45
  linux-image-4.4.0-1074-aws      4.4.0-1074.84
  linux-image-4.4.0-1102-raspi2   4.4.0-1102.110
  linux-image-4.4.0-1106-snapdragon  4.4.0-1106.111
  linux-image-4.4.0-141-generic   4.4.0-141.167
  linux-image-4.4.0-141-generic-lpae  4.4.0-141.167
  linux-image-4.4.0-141-lowlatency  4.4.0-141.167
  linux-image-4.4.0-141-powerpc-e500mc  4.4.0-141.167
  linux-image-4.4.0-141-powerpc-smp  4.4.0-141.167
  linux-image-4.4.0-141-powerpc64-emb  4.4.0-141.167
  linux-image-4.4.0-141-powerpc64-smp  4.4.0-141.167
  linux-image-aws                 4.4.0.1074.76
  linux-image-generic             4.4.0.141.147
  linux-image-generic-lpae        4.4.0.141.147
  linux-image-kvm                 4.4.0.1039.38
  linux-image-lowlatency          4.4.0.141.147
  linux-image-powerpc-e500mc      4.4.0.141.147
  linux-image-powerpc-smp         4.4.0.141.147
  linux-image-powerpc64-emb       4.4.0.141.147
  linux-image-powerpc64-smp       4.4.0.141.147
  linux-image-raspi2              4.4.0.1102.102
  linux-image-snapdragon          4.4.0.1106.98

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.