Ubuntu 16.04 LTS Security Advisory USN-4286-1: Critical Kernel Flaws

ubuntu

February 18, 2020

Several security issues were fixed in the Linux kernel.

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 the Linux kernel did not properly clear data

structures on context switches for certain Intel graphics processors. A

local attacker could use this to expose sensitive information.

(CVE-2019-14615)

It was discovered that a race condition existed in the Softmac USB Prism54

device driver in the Linux kernel. A physically proximate attacker could

use this to cause a denial of service (system crash). (CVE-2019-15220)

Julien Grall discovered that the Xen balloon memory driver in the Linux

kernel did not properly restrict the amount of memory set aside for page

mappings in some situations. An attacker could use this to cause a denial

of se...

Read the Full Advisory

Topics Covered

security advisory denial of service kernel local attack ubuntu memory exhaustion system crash

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1066-kvm      4.4.0-1066.73
  linux-image-4.4.0-1102-aws      4.4.0-1102.113
  linux-image-4.4.0-1129-raspi2   4.4.0-1129.138
  linux-image-4.4.0-1133-snapdragon  4.4.0-1133.141
  linux-image-4.4.0-174-generic   4.4.0-174.204
  linux-image-4.4.0-174-generic-lpae  4.4.0-174.204
  linux-image-4.4.0-174-lowlatency  4.4.0-174.204
  linux-image-4.4.0-174-powerpc-e500mc  4.4.0-174.204
  linux-image-4.4.0-174-powerpc-smp  4.4.0-174.204
  linux-image-4.4.0-174-powerpc64-emb  4.4.0-174.204
  linux-image-4.4.0-174-powerpc64-smp  4.4.0-174.204
  linux-image-aws                 4.4.0.1102.106
  linux-image-generic             4.4.0.174.182
  linux-image-generic-lpae        4.4.0.174.182
  linux-image-kvm                 4.4.0.1066.66
  linux-image-lowlatency          4.4.0.174.182
  linux-image-powerpc-e500mc      4.4.0.174.182
  linux-image-powerpc-smp         4.4.0.174.182
  linux-image-powerpc64-emb       4.4.0.174.182
  linux-image-powerpc64-smp       4.4.0.174.182
  linux-image-raspi2              4.4.0.1129.129
  linux-image-snapdragon          4.4.0.1133.125
  linux-image-virtual             4.4.0.174.182

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.