=========================================================================Ubuntu Security Notice USN-2840-1
December 17, 2015

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

- Ubuntu 12.04 LTS

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

Dmitry Vyukov discovered that the Linux kernel's keyring handler attempted
to garbage collect incompletely instantiated keys. A local unprivileged
attacker could use this to cause a denial of service (system crash).
(CVE-2015-7872)

Jan Beulich discovered that the KVM svm hypervisor implementation in the
Linux kernel did not properly catch Debug exceptions on AMD processors. An
attacker in a guest virtual machine could use this to cause a denial of
service (system crash) in the host OS. (CVE-2015-8104)

Update instructions:

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

Ubuntu 12.04 LTS:
  linux-image-3.2.0-96-generic    3.2.0-96.136
  linux-image-3.2.0-96-generic-pae  3.2.0-96.136
  linux-image-3.2.0-96-highbank   3.2.0-96.136
  linux-image-3.2.0-96-omap       3.2.0-96.136
  linux-image-3.2.0-96-powerpc-smp  3.2.0-96.136
  linux-image-3.2.0-96-powerpc64-smp  3.2.0-96.136
  linux-image-3.2.0-96-virtual    3.2.0-96.136

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-2840-1
  CVE-2015-7872, CVE-2015-8104

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.2.0-96.136