1. Ubuntu Security Notices
  2. USN-3169-2

USN-3169-2: Linux kernel (Xenial HWE) vulnerabilities

Publication date

11 January 2017

Overview

Several security issues were fixed in the kernel.

Releases

Packages

Details

USN-3169-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04
LTS. This update provides the corresponding updates for the Linux
Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu
14.04 LTS.

Dmitry Vyukov discovered that the KVM implementation in the Linux kernel
did not properly initialize the Code Segment (CS) in certain error cases. A
local attacker could use this to expose sensitive information (kernel
memory). (CVE-2016-9756)

Andrey Konovalov discovered that signed integer overflows existed in the
setsockopt() system call when handling the SO_SNDBUFFORCE and
SO_RCVBUFFORCE options. A local attacker with the CAP_NET_ADMIN capability
could use this to cause a denial of service (system crash or memory
corruption). (CVE-2016-9793)

Baozeng Ding discovered a race condition that could lead to a use-after-
free in the...

USN-3169-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04
LTS. This update provides the corresponding updates for the Linux
Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu
14.04 LTS.

Dmitry Vyukov discovered that the KVM implementation in the Linux kernel
did not properly initialize the Code Segment (CS) in certain error cases. A
local attacker could use this to expose sensitive information (kernel
memory). (CVE-2016-9756)

Andrey Konovalov discovered that signed integer overflows existed in the
setsockopt() system call when handling the SO_SNDBUFFORCE and
SO_RCVBUFFORCE options. A local attacker with the CAP_NET_ADMIN capability
could use this to cause a denial of service (system crash or memory
corruption). (CVE-2016-9793)

Baozeng Ding discovered a race condition that could lead to a use-after-
free in the Advanced Linux Sound Architecture (ALSA) subsystem of the Linux
kernel. A local attacker could use this to cause a denial of service
(system crash). (CVE-2016-9794)

Update instructions

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

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
14.04 trusty linux-image-4.4.0-59-generic –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-generic-lpae –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-lowlatency –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-powerpc-e500mc –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-powerpc-smp –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-powerpc64-emb –  4.4.0-59.80~14.04.1
linux-image-4.4.0-59-powerpc64-smp –  4.4.0-59.80~14.04.1

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Get Ubuntu Pro

References

Have additional questions?

Talk to a member of the team ›