14 DAY TRIAL // Canonical has announced today, April 30, that new kernel updates are available for its Ubuntu 14.04 LTS (Trusty Tahr) and Ubuntu 12.04 LTS (Precise Pangolin) operating systems.
All users are urged to upgrade their Ubuntu machines as soon as possible, as the new kernel updates are here to patch various security issues that have been discovered recently in the upstream Linux kernel.
The new kernels are linux-image-3.13.0-51 (3.13.0-51.84) for Ubuntu 14.04 LTS (Trusty Tahr) and linux-image-3.2.0-82 (3.2.0-82.119) for Ubuntu 12.04 LTS (Precise Pangolin).
How to update the kernels on Ubuntu 14.04 and 12.04 LTS
To update, open the Unity Dash, search for the Software Updater application, open it, wait for the update channels to be refreshed, and apply any available updated packages.
After a kernel update, you will have to reboot your machine. Then, make sure that the new kernels match with the ones listed above by running the "uname -a" command (without quotes) in the Terminal app.
Alternatively, you can update the kernels in Ubuntu 14.04 LTS and Ubuntu 12.04 LTS from the Terminal app, by executing the "sudo apt-get update && sudo apt-get dist-upgrade" command (without quotes).
Three kernel vulnerabilities were patched in Ubuntu 14.04 and 12.04
Two kernel vulnerabilities were patched in the Ubuntu 14.04 LTS (Trusty Tahr) operating system, and only one in the Ubuntu 12.04 LTS (Precise Pangolin) distribution. But one of them is common to both releases.
Therefore, it was discovered that a stack overflow in the microcode loader for the Intel x86 platform could allow a local attacker to cause a kernel crash or run code with kernel privileges. This was patched in Ubuntu 14.04 LTS.
In addition, a flaw in Linux kernel's IPv6 networking stack that could allow an unprivileged attacker on a local network to cause a denial of service (DoS) attack was patched in both Ubuntu 14.04 LTS and Ubuntu 12.04 LTS.