==========================================================================
Ubuntu Security Notice USN-2516-3
March 04, 2015

linux vulnerabilities regression
==========================================================================

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

- Ubuntu 14.04 LTS

Summary:

USN-2516-1 introduced a regression in the Linux kernel.

Software Description:
- linux: Linux kernel

Details:

USN-2516-1 fixed vulnerabilities in the Linux kernel, and the fix in
USN-2516-2 was incomplete. There was an unrelated regression in the use of
the virtual counter (CNTVCT) on arm64 architectures.

This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

A flaw was discovered in the Kernel Virtual Machine's (KVM) emulation of
the SYSTENTER instruction when the guest OS does not initialize the
SYSENTER MSRs. A guest OS user could exploit this flaw to cause a denial of
service of the guest OS (crash) or potentially gain privileges on the guest
OS. (CVE-2015-0239)

Andy Lutomirski discovered an information leak in the Linux kernel's Thread
Local Storage (TLS) implementation allowing users to bypass the espfix to
obtain information that could be used to bypass the Address Space Layout
Randomization (ASLR) protection mechanism. A local user could exploit this
flaw to obtain potentially sensitive information from kernel memory.
(CVE-2014-8133)

A restriction bypass was discovered in iptables when conntrack rules are
specified and the conntrack protocol handler module is not loaded into the
Linux kernel. This flaw can cause the firewall rules on the system to be
bypassed when conntrack rules are used. (CVE-2014-8160)

A flaw was discovered with file renaming in the linux kernel. A local user
could exploit this flaw to cause a denial of service (deadlock and system
hang). (CVE-2014-8559)

A flaw was discovered in how supplemental group memberships are handled in
certain namespace scenarios. A local user could exploit this flaw to bypass
file permission restrictions. (CVE-2014-8989)

A flaw was discovered in how Thread Local Storage (TLS) is handled by the
task switching function in the Linux kernel for x86_64 based machines. A
local user could exploit this flaw to bypass the Address Space Layout
Radomization (ASLR) protection mechanism. (CVE-2014-9419)

Prasad J Pandit reported a flaw in the rock_continue function of the Linux
kernel's ISO 9660 CDROM file system. A local user could exploit this flaw
to cause a denial of service (system crash or hang). (CVE-2014-9420)

A flaw was discovered in the fragment handling of the B.A.T.M.A.N. Advanced
Meshing Protocol in the Linux kernel. A remote attacker could exploit this
flaw to cause a denial of service (mesh-node system crash) via fragmented
packets. (CVE-2014-9428)

A race condition was discovered in the Linux kernel's key ring. A local
user could cause a denial of service (memory corruption or panic) or
possibly have unspecified impact via the keyctl commands. (CVE-2014-9529)

A memory leak was discovered in the ISO 9660 CDROM file system when parsing
rock ridge ER records. A local user could exploit this flaw to obtain
sensitive information from kernel memory via a crafted iso9660 image.
(CVE-2014-9584)

A flaw was discovered in the Address Space Layout Randomization (ASLR) of
the Virtual Dynamically linked Shared Objects (vDSO) location. This flaw
makes it easier for a local user to bypass the ASLR protection mechanism.
(CVE-2014-9585)

Dmitry Chernenkov discovered a buffer overflow in eCryptfs' encrypted file
name decoding. A local unprivileged user could exploit this flaw to cause a
denial of service (system crash) or potentially gain administrative
privileges. (CVE-2014-9683)

Update instructions:

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

Ubuntu 14.04 LTS:
  linux-image-3.13.0-46-generic   3.13.0-46.77
  linux-image-3.13.0-46-generic-lpae  3.13.0-46.77
  linux-image-3.13.0-46-lowlatency  3.13.0-46.77
  linux-image-3.13.0-46-powerpc-e500  3.13.0-46.77
  linux-image-3.13.0-46-powerpc-e500mc  3.13.0-46.77
  linux-image-3.13.0-46-powerpc-smp  3.13.0-46.77
  linux-image-3.13.0-46-powerpc64-emb  3.13.0-46.77
  linux-image-3.13.0-46-powerpc64-smp  3.13.0-46.77

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  http://www.ubuntu.com/usn/usn-2516-3
  http://www.ubuntu.com/usn/usn-2516-1
  https://launchpad.net/bugs/1427292

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.13.0-46.77