Ubuntu 16.04 LTS USN-3220-1 Critical: Denial Of Service Risk

ubuntu

March 8, 2017

The system could be made to crash or run programs as an administrator.

Summary

The system could be made to crash or run programs as an administrator.

Software Description:

- linux: Linux kernel

- linux-gke: Linux kernel for Google Container Engine (GKE) systems

- linux-raspi2: Linux kernel for Raspberry Pi 2

- linux-snapdragon: Linux kernel for Snapdragon Processors

Details:

Alexander Popov discovered that the N_HDLC line discipline implementation

in the Linux kernel contained a double-free vulnerability. A local attacker

could use this to cause a denial of service (system crash) or possibly gain

administrative privileges.

Topics Covered

security advisory denial of service update kernel ubuntu administrative access

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1005-gke      4.4.0-1005.6
  linux-image-4.4.0-1046-raspi2   4.4.0-1046.53
  linux-image-4.4.0-1050-snapdragon  4.4.0-1050.54
  linux-image-4.4.0-66-generic    4.4.0-66.87
  linux-image-4.4.0-66-generic-lpae  4.4.0-66.87
  linux-image-4.4.0-66-lowlatency  4.4.0-66.87
  linux-image-4.4.0-66-powerpc-e500mc  4.4.0-66.87
  linux-image-4.4.0-66-powerpc-smp  4.4.0-66.87
  linux-image-4.4.0-66-powerpc64-emb  4.4.0-66.87
  linux-image-4.4.0-66-powerpc64-smp  4.4.0-66.87
  linux-image-generic             4.4.0.66.70
  linux-image-generic-lpae        4.4.0.66.70
  linux-image-gke                 4.4.0.1005.5
  linux-image-lowlatency          4.4.0.66.70
  linux-image-powerpc-e500mc      4.4.0.66.70
  linux-image-powerpc-smp         4.4.0.66.70
  linux-image-powerpc64-emb       4.4.0.66.70
  linux-image-powerpc64-smp       4.4.0.66.70
  linux-image-raspi2              4.4.0.1046.45
  linux-image-snapdragon          4.4.0.1050.42

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.