Ubuntu Security Notice USN-3522-3
10th January, 2018
A security issue affects these releases of Ubuntu and its
- Ubuntu 16.04 LTS
USN-3522-1 introduced a regression in the Linux kernel.
– Linux kernel
USN-3522-1 fixed a vulnerability in the Linux kernel to address
Meltdown (CVE-2017-5754). Unfortunately, that update introduced
a regression where a few systems failed to boot successfully. This
update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Jann Horn discovered that microprocessors utilizing speculative execution
and indirect branch prediction may allow unauthorized memory reads via
sidechannel attacks. This flaw is known as Meltdown. A local attacker could
use this to expose sensitive information, including kernel memory.
The problem can be corrected by updating your system to the following
- Ubuntu 16.04 LTS:
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.