USN-3160-1: Linux kernel vulnerabilities

Ubuntu Security Notice USN-3160-1

20th December, 2016

linux vulnerabilities

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

  • Ubuntu 14.04 LTS


Several security issues were fixed in the kernel.

Software description

  • linux - Linux kernel


CAI Qian discovered that shared bind mounts in a mount namespace
exponentially added entries without restriction to the Linux kernel's mount
table. A local attacker could use this to cause a denial of service (system
crash). (CVE-2016-6213)

It was discovered that a race condition existed in the procfs
environ_read function in the Linux kernel, leading to an integer
underflow. A local attacker could use this to expose sensitive
information (kernel memory). (CVE-2016-7916)

Update instructions

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

Ubuntu 14.04 LTS:
linux-image-3.13.0-106-powerpc64-emb 3.13.0-106.153
linux-image-3.13.0-106-lowlatency 3.13.0-106.153
linux-image-3.13.0-106-generic 3.13.0-106.153
linux-image-3.13.0-106-generic-lpae 3.13.0-106.153
linux-image-3.13.0-106-powerpc-e500mc 3.13.0-106.153
linux-image-3.13.0-106-powerpc-e500 3.13.0-106.153
linux-image-3.13.0-106-powerpc-smp 3.13.0-106.153
linux-image-3.13.0-106-powerpc64-smp 3.13.0-106.153

To update your system, please follow these instructions:

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.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.


CVE-2016-6213, CVE-2016-7916