USN-3484-2: Linux kernel (HWE) vulnerability
Ubuntu Security Notice USN-3484-2
21st November, 2017
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 16.04 LTS
The system could be made to crash or run programs as an administrator.
- linux-hwe - Linux hardware enablement (HWE) kernel
USN-3484-1 fixed vulnerabilities in the Linux kernel for Ubuntu 17.04.
This update provides the corresponding updates for the Linux Hardware
Enablement (HWE) kernel from Ubuntu 17.04 for Ubuntu 16.04 LTS.
It was discovered that the KVM subsystem in the Linux kernel did not
properly keep track of nested levels in guest page tables. A local attacker
in a guest VM could use this to cause a denial of service (host OS crash)
or possibly execute arbitrary code in the host OS.
The problem can be corrected by updating your system to the following package version:
- Ubuntu 16.04 LTS:
- linux-image-4.10.0-40-generic 4.10.0-40.44~16.04.1
- linux-image-4.10.0-40-lowlatency 4.10.0-40.44~16.04.1
- linux-image-generic-hwe-16.04 188.8.131.52.42
- linux-image-4.10.0-40-generic-lpae 4.10.0-40.44~16.04.1
- linux-image-lowlatency-hwe-16.04 184.108.40.206.42
- linux-image-generic-lpae-hwe-16.04 220.127.116.11.42
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
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.