Ubuntu 16.04 LTS: USN-4320-1 Critical: Kernel Crash and Info Leak

ubuntu

April 6, 2020

The system could be made to crash or expose sensitive information.

Summary

The system could be made to crash or expose sensitive information.

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- linux-lts-xenial: Linux hardware enablement kernel from Xenial for

Trusty

Details:

Al Viro discovered that the vfs layer in the Linux kernel contained a use-

after-free vulnerability. A local attacker could use this to cause a denial

of service (system crash) or possibly expose sensitive information (kernel

memory).

Topics Covered

security advisory denial of service kernel ubuntu sensitive information linux-raspi2

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1069-kvm      4.4.0-1069.76
  linux-image-4.4.0-1105-aws      4.4.0-1105.116
  linux-image-4.4.0-1131-raspi2   4.4.0-1131.140
  linux-image-4.4.0-1135-snapdragon  4.4.0-1135.143
  linux-image-4.4.0-177-generic   4.4.0-177.207
  linux-image-4.4.0-177-generic-lpae  4.4.0-177.207
  linux-image-4.4.0-177-lowlatency  4.4.0-177.207
  linux-image-4.4.0-177-powerpc-e500mc  4.4.0-177.207
  linux-image-4.4.0-177-powerpc-smp  4.4.0-177.207
  linux-image-4.4.0-177-powerpc64-emb  4.4.0-177.207
  linux-image-4.4.0-177-powerpc64-smp  4.4.0-177.207
  linux-image-aws                 4.4.0.1105.109
  linux-image-generic             4.4.0.177.185
  linux-image-generic-lpae        4.4.0.177.185
  linux-image-kvm                 4.4.0.1069.69
  linux-image-lowlatency          4.4.0.177.185
  linux-image-powerpc-e500mc      4.4.0.177.185
  linux-image-powerpc-smp         4.4.0.177.185
  linux-image-powerpc64-emb       4.4.0.177.185
  linux-image-powerpc64-smp       4.4.0.177.185
  linux-image-raspi2              4.4.0.1131.131
  linux-image-snapdragon          4.4.0.1135.127
  linux-image-virtual             4.4.0.177.185

Ubuntu 14.04 ESM:
  linux-image-4.4.0-1065-aws      4.4.0-1065.69
  linux-image-4.4.0-177-generic   4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-generic-lpae  4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-lowlatency  4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-powerpc-e500mc  4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-powerpc-smp  4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-powerpc64-emb  4.4.0-177.207~14.04.1
  linux-image-4.4.0-177-powerpc64-smp  4.4.0-177.207~14.04.1
  linux-image-aws                 4.4.0.1065.66
  linux-image-generic-lpae-lts-xenial  4.4.0.177.156
  linux-image-generic-lts-xenial  4.4.0.177.156
  linux-image-lowlatency-lts-xenial  4.4.0.177.156
  linux-image-powerpc-e500mc-lts-xenial  4.4.0.177.156
  linux-image-powerpc-smp-lts-xenial  4.4.0.177.156
  linux-image-powerpc64-emb-lts-xenial  4.4.0.177.156
  linux-image-powerpc64-smp-lts-xenial  4.4.0.177.156
  linux-image-virtual-lts-xenial  4.4.0.177.156

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.