============================================================================
Ubuntu Security Notice USN-1768-1
March 18, 2013

linux-lts-quantal 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-lts-quantal: Linux hardware enablement kernel from Quantal

Details:

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)

A failure to validate input was discovered in the Linux kernel's Xen
netback (network backend) driver. A user in a guest OS may exploit this
flaw to cause a denial of service to the guest OS and other guest domains.
(CVE-2013-0216)

A memory leak was discovered in the Linux kernel's Xen netback (network
backend) driver. A user in a guest OS could trigger this flaw to cause a
denial of service on the system. (CVE-2013-0217)

A flaw was discovered in the Linux kernel Xen PCI backend driver. If a PCI
device is assigned to the guest OS, the guest OS could exploit this flaw to
cause a denial of service on the host. (CVE-2013-0231)

A flaw was reported in the permission checks done by the Linux kernel for
/dev/cpu/*/msr. A local root user with all capabilities dropped could
exploit this flaw to execute code with full root capabilities.
(CVE-2013-0268)

Tommi Rantala discovered a flaw in the a flaw the Linux kernels handling of
datagrams packets when the MSG_PEEK flag is specified. An unprivileged
local user could exploit this flaw to cause a denial of service (system
hang). (CVE-2013-0290)

A flaw was discovered in the Linux kernel's vhost driver used to accelerate
guest networking in KVM based virtual machines. A privileged guest user
could exploit this flaw to crash the host system. (CVE-2013-0311)

A flaw was discovered in the Extended Verification Module (EVM) of the
Linux kernel. An unprivileged local user code exploit this flaw to cause a
denial of service (system crash). (CVE-2013-0313)

An information leak was discovered in the Linux kernel's Bluetooth stack
when HIDP (Human Interface Device Protocol) support is enabled. A local
unprivileged user could exploit this flaw to cause an information leak from
the kernel. (CVE-2013-0349)

Update instructions:

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

Ubuntu 12.04 LTS:
  linux-image-3.5.0-26-generic    3.5.0-26.42~precise1

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://www.ubuntu.com/usn/usn-1768-1
  CVE-2013-0190, CVE-2013-0216, CVE-2013-0217, CVE-2013-0231,
  CVE-2013-0268, CVE-2013-0290, CVE-2013-0311, CVE-2013-0313,
  CVE-2013-0349

Package Information:
  https://launchpad.net/ubuntu/+source/linux-lts-quantal/3.5.0-26.42~precise1