14 DAY TRIAL // Canonical released new kernel security updates for all of its supported Ubuntu Linux operating systems, including Ubuntu 17.04 (Zesty Zapus), Ubuntu 16.04 LTS (Xenial Xerus), Ubuntu 16.10 (Yakkety Yak), and Ubuntu 14.04 LTS (Trusty Tahr).
While the kernel update for Ubuntu 16.10 systems patches buffer overflow discovered in Linux kernel's trace subsystem, which could have allowed a local privileged attacker to execute arbitrary code, it looks like a total of 15 and 13 kernel vulnerabilities were patched for Ubuntu 17.04 and Ubuntu 16.04 LTS machines, respectively. Check here and here for details on what's been patched.
For Ubuntu 16.04 LTS (Xenial Xerus), users will have to install the linux-image-4.4.0-79 (4.4.0-79.100) kernel package on 64-bit and 32-bit PCs, linux-image-4.4.0-1018-aws (4.4.0-1018.27) on Amazon Web Services (AWS) systems, and linux-image-4.4.0-1014-gke (4.4.0-1014.14) on Google Container Engine (GKE) systems.
Additionally, you need to install the linux-image-4.4.0-1057-raspi2 4.4.0-1057.64 kernel on Ubuntu 16.04 LTS for Raspberry Pi 2 systems and linux-image-4.4.0-1059-snapdragon (4.4.0-1059.63) on Snapdragon processors. An HWE kernel is also available for Ubuntu 16.04.2 LTS users, namely linux-image-4.8.0-54 (4.8.0-54.57~16.04.1).
Users are urged to update their installations as soon as possible
On the other hand, if you're running the Ubuntu 17.04 (Zesty Zapus) operating system, you'll need to install the linux-image 4.10.0.22.24 kernel packages on 64-bit and 32-bit machines, as well as the linux-image-raspi2 4.10.0.1006.8 kernel on Ubuntu 17.04 for Raspberry Pi 2 computers.
Canonical also released an HWE (hardware enablement) kernel for users of Ubuntu 14.04.5 LTS (Trusty Tahr) operating systems using the Linux kernel packages of Ubuntu 16.04 LTS (Xenial Xerus). All users are urged to update their installations as soon as possible by following the instructions at https://wiki.ubuntu.com/Security/Upgrades.