============================================================================
Ubuntu Security Notice USN-2421-1
November 25, 2014

linux vulnerabilities
============================================================================

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

- Ubuntu 14.10

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

A flaw was discovered in how the Linux kernel's KVM (Kernel Virtual
Machine) subsystem handles the CR4 control register at VM entry on Intel
processors. A local host OS user can exploit this to cause a denial of
service (kill arbitrary processes, or system disruption) by leveraging
/dev/kvm access. (CVE-2014-3690)

Don Bailey discovered a flaw in the LZO decompress algorithm used by the
Linux kernel. An attacker could exploit this flaw to cause a denial of
service (memory corruption or OOPS). (CVE-2014-4608)

Andy Lutomirski discovered that the Linux kernel was not checking the
CAP_SYS_ADMIN when remounting filesystems to read-only. A local user could
exploit this flaw to cause a denial of service (loss of writability).
(CVE-2014-7975)

Update instructions:

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

Ubuntu 14.10:
  linux-image-3.16.0-25-generic   3.16.0-25.33
  linux-image-3.16.0-25-generic-lpae  3.16.0-25.33
  linux-image-3.16.0-25-lowlatency  3.16.0-25.33
  linux-image-3.16.0-25-powerpc-e500mc  3.16.0-25.33
  linux-image-3.16.0-25-powerpc-smp  3.16.0-25.33
  linux-image-3.16.0-25-powerpc64-emb  3.16.0-25.33
  linux-image-3.16.0-25-powerpc64-smp  3.16.0-25.33

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:
  http://www.ubuntu.com/usn/usn-2421-1
  CVE-2014-3690, CVE-2014-4608, CVE-2014-7975

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.16.0-25.33