Ubuntu: 1720-1: Linux kernel vulnerabilities
Posted by Benjamin D. Thomas   
Ubuntu Several security issues were fixed in the kernel.
==========================================================================
Ubuntu Security Notice USN-1720-1
February 12, 2013

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

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

- Ubuntu 11.10

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

It was discovered that hypervkvpd, which is distributed in the Linux
kernel, was not correctly validating the origin on Netlink messages. An
untrusted local user can cause a denial of service of Linux guests in
Hyper-V virtualization environments. (CVE-2012-2669)

Dmitry Monakhov reported a race condition flaw the Linux ext4 filesystem
that can expose stale data. An unprivileged user could exploit this flaw to
cause an information leak. (CVE-2012-4508)

Florian Weimer discovered that hypervkvpd, which is distributed in the
Linux kernel, was not correctly validating source addresses of netlink
packets. An untrusted local user can cause a denial of service by causing
hypervkvpd to exit. (CVE-2012-5532)

Andrew Cooper of Citrix reported a Xen stack corruption in the Linux
kernel. An unprivileged user in a 32bit PVOPS guest can cause the guest
kernel to crash, or operate erroneously. (CVE-2013-0190)

Update instructions:

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

Ubuntu 11.10:
  linux-image-3.0.0-31-generic    3.0.0-31.48
  linux-image-3.0.0-31-generic-pae  3.0.0-31.48
  linux-image-3.0.0-31-omap       3.0.0-31.48
  linux-image-3.0.0-31-powerpc    3.0.0-31.48
  linux-image-3.0.0-31-powerpc-smp  3.0.0-31.48
  linux-image-3.0.0-31-powerpc64-smp  3.0.0-31.48
  linux-image-3.0.0-31-server     3.0.0-31.48
  linux-image-3.0.0-31-virtual    3.0.0-31.48

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-1720-1
  CVE-2012-2669, CVE-2012-4508, CVE-2012-5532, CVE-2013-0190

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.0.0-31.48