USN-3848-1: Linux kernel vulnerabilities

20 December 2018

linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 16.04 LTS

Summary

Several security issues were fixed in the Linux kernel.

Software Description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

It was discovered that a double free existed in the AMD GPIO driver in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-18174)

It was discovered that an integer overrun vulnerability existed in the POSIX timers implementation in the Linux kernel. A local attacker could use this to cause a denial of service. (CVE-2018-12896)

Kanda Motohiro discovered that writing extended attributes to an XFS file system in the Linux kernel in certain situations could cause an error condition to occur. A local attacker could use this to cause a denial of service. (CVE-2018-18690)

It was discovered that an integer overflow vulnerability existed in the CDROM driver of the Linux kernel. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2018-18710)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 16.04 LTS
linux-image-4.4.0-1039-kvm - 4.4.0-1039.45
linux-image-4.4.0-1074-aws - 4.4.0-1074.84
linux-image-4.4.0-1102-raspi2 - 4.4.0-1102.110
linux-image-4.4.0-1106-snapdragon - 4.4.0-1106.111
linux-image-4.4.0-141-generic - 4.4.0-141.167
linux-image-4.4.0-141-generic-lpae - 4.4.0-141.167
linux-image-4.4.0-141-lowlatency - 4.4.0-141.167
linux-image-4.4.0-141-powerpc-e500mc - 4.4.0-141.167
linux-image-4.4.0-141-powerpc-smp - 4.4.0-141.167
linux-image-4.4.0-141-powerpc64-emb - 4.4.0-141.167
linux-image-4.4.0-141-powerpc64-smp - 4.4.0-141.167
linux-image-aws - 4.4.0.1074.76
linux-image-generic - 4.4.0.141.147
linux-image-generic-lpae - 4.4.0.141.147
linux-image-kvm - 4.4.0.1039.38
linux-image-lowlatency - 4.4.0.141.147
linux-image-powerpc-e500mc - 4.4.0.141.147
linux-image-powerpc-smp - 4.4.0.141.147
linux-image-powerpc64-emb - 4.4.0.141.147
linux-image-powerpc64-smp - 4.4.0.141.147
linux-image-raspi2 - 4.4.0.1102.102
linux-image-snapdragon - 4.4.0.1106.98

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.

References