=========================================================================Ubuntu Security Notice USN-2852-1
December 19, 2015

linux-raspi2 vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 15.10

Summary:

The system could be made to provide access outside of namespace sandbox.

Software Description:
- linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

Jann Horn discovered a ptrace issue with user namespaces in the Linux
kernel. The namespace owner could potentially exploit this flaw by ptracing
a root owned process entering the user namespace to elevate its privileges
and potentially gain access outside of the namespace.
(https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1527374)

Update instructions:

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

Ubuntu 15.10:
  linux-image-4.2.0-1017-raspi2   4.2.0-1017.24

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://ubuntu.com/security/notices/USN-2852-1
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1527374

Package Information:
  https://launchpad.net/ubuntu/+source/linux-raspi2/4.2.0-1017.24