============================================================================
Ubuntu Security Notice USN-2417-1
November 25, 2014

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:

Nadav Amit reported that the KVM (Kernel Virtual Machine) mishandles
noncanonical addresses when emulating instructions that change the rip
(Instruction Pointer). A guest user with access to I/O or the MMIO can use
this flaw to cause a denial of service (system crash) of the guest.
(CVE-2014-3647)

A flaw was discovered with the handling of the invept instruction in the
KVM (Kernel Virtual Machine) subsystem of the Linux kernel. An unprivileged
guest user could exploit this flaw to cause a denial of service (system
crash) on the guest. (CVE-2014-3646)

A flaw was discovered with invept instruction support when using nested EPT
in the KVM (Kernel Virtual Machine). An unprivileged guest user could
exploit this flaw to cause a denial of service (system crash) on the guest.
(CVE-2014-3645)

Lars Bull reported a race condition in the PIT (programmable interrupt
timer) emulation in the KVM (Kernel Virtual Machine) subsystem of the Linux
kernel. A local guest user with access to PIT i/o ports could exploit this
flaw to cause a denial of service (crash) on the host. (CVE-2014-3611)

Lars Bull and Nadav Amit reported a flaw in how KVM (the Kernel Virtual
Machine) handles noncanonical writes to certain MSR registers. A privileged
guest user can exploit this flaw to cause a denial of service (kernel
panic) on the host. (CVE-2014-3610)

A flaw in the handling of malformed ASCONF chunks by SCTP (Stream Control
Transmission Protocol) implementation in the Linux kernel was discovered. A
remote attacker could exploit this flaw to cause a denial of service
(system crash). (CVE-2014-3673)

A flaw in the handling of duplicate ASCONF chunks by SCTP (Stream Control
Transmission Protocol) implementation in the Linux kernel was discovered. A
remote attacker could exploit this flaw to cause a denial of service
(panic). (CVE-2014-3687)

It was discovered that excessive queuing by SCTP (Stream Control
Transmission Protocol) implementation in the Linux kernel can cause memory
pressure. A remote attacker could exploit this flaw to cause a denial of
service. (CVE-2014-3688)

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)

It was discovered the Linux kernel's implementation of IPv6 did not
properly validate arguments in the ipv6_select_ident function. A local user
could exploit this flaw to cause a denial of service (system crash) by
leveraging tun or macvtap device access. (CVE-2014-7207)

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 12.04 LTS:
  linux-image-3.2.0-72-generic    3.2.0-72.107
  linux-image-3.2.0-72-generic-pae  3.2.0-72.107
  linux-image-3.2.0-72-highbank   3.2.0-72.107
  linux-image-3.2.0-72-omap       3.2.0-72.107
  linux-image-3.2.0-72-powerpc-smp  3.2.0-72.107
  linux-image-3.2.0-72-powerpc64-smp  3.2.0-72.107
  linux-image-3.2.0-72-virtual    3.2.0-72.107

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-2417-1
  CVE-2014-3610, CVE-2014-3611, CVE-2014-3645, CVE-2014-3646,
  CVE-2014-3647, CVE-2014-3673, CVE-2014-3687, CVE-2014-3688,
  CVE-2014-3690, CVE-2014-4608, CVE-2014-7207, CVE-2014-7975

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.2.0-72.107