=========================================================================Ubuntu Security Notice USN-2643-1
June 15, 2015

linux vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 14.04 LTS

Summary:

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

Software Description:
- linux: Linux kernel

Details:

Philip Pettersson discovered a privilege escalation when using overlayfs
mounts inside of user namespaces. A local user could exploit this flaw to
gain administrative privileges on the system.

Update instructions:

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

Ubuntu 14.04 LTS:
  linux-image-3.13.0-55-generic   3.13.0-55.92
  linux-image-3.13.0-55-generic-lpae  3.13.0-55.92
  linux-image-3.13.0-55-lowlatency  3.13.0-55.92
  linux-image-3.13.0-55-powerpc-e500  3.13.0-55.92
  linux-image-3.13.0-55-powerpc-e500mc  3.13.0-55.92
  linux-image-3.13.0-55-powerpc-smp  3.13.0-55.92
  linux-image-3.13.0-55-powerpc64-emb  3.13.0-55.92
  linux-image-3.13.0-55-powerpc64-smp  3.13.0-55.92

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. If
you use linux-restricted-modules, you have to update that package as
well to get modules which work with the new kernel version. Unless you
manually uninstalled the standard kernel metapackages (e.g. linux-generic,
linux-server, linux-powerpc), a standard system upgrade will automatically
perform this as well.

References:
  https://ubuntu.com/security/notices/USN-2643-1
  CVE-2015-1328

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.13.0-55.92