1. Ubuntu Security Notices
  2. USN-3630-2

USN-3630-2: Linux kernel (HWE) vulnerability

Publication date

24 April 2018

Overview

The system could be made to crash under certain conditions.

Releases

Packages

  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oem - Linux kernel for OEM processors

Details

USN-3630-1 fixed a vulnerability in the Linux kernel for Ubuntu 17.10.
This update provides the corresponding updates for the Linux Hardware
Enablement (HWE) kernel from Ubuntu 17.10 for Ubuntu 16.04 LTS.

It was discovered that the Broadcom UniMAC MDIO bus controller driver in
the Linux kernel did not properly validate device resources. A local
attacker could use this to cause a denial of service (system crash).

USN-3630-1 fixed a vulnerability in the Linux kernel for Ubuntu 17.10.
This update provides the corresponding updates for the Linux Hardware
Enablement (HWE) kernel from Ubuntu 17.10 for Ubuntu 16.04 LTS.

It was discovered that the Broadcom UniMAC MDIO bus controller driver in
the Linux kernel did not properly validate device resources. A local
attacker could use this to cause a denial of service (system crash).

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
16.04 xenial linux-image-4.13.0-1013-gcp –  4.13.0-1013.17
linux-image-4.13.0-1024-oem –  4.13.0-1024.27
linux-image-4.13.0-39-generic –  4.13.0-39.44~16.04.1
linux-image-4.13.0-39-generic-lpae –  4.13.0-39.44~16.04.1
linux-image-4.13.0-39-lowlatency –  4.13.0-39.44~16.04.1

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 ›