Ubuntu 16.04 LTS: USN-3265-1 Critical: Kernel System Crash

ubuntu

April 25, 2017

Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux: Linux kernel

- linux-aws: Linux kernel for Amazon Web Services (AWS) systems

- linux-gke: Linux kernel for Google Container Engine (GKE) systems

- linux-raspi2: Linux kernel for Raspberry Pi 2

- linux-snapdragon: Linux kernel for Snapdragon Processors

Details:

It was discovered that a use-after-free flaw existed in the filesystem

encryption subsystem in the Linux kernel. A local attacker could use this

to cause a denial of service (system crash). (CVE-2017-7374)

Andrey Konovalov discovered an out-of-bounds access in the IPv6 Generic

Routing Encapsulation (GRE) tunneling implementation in the Linux kernel.

An attacker could use this to possibly expose sensitive information.

(CVE-2017-5897)

Andrey Konovalov discovered that the IPv4 implementation in the Linux

kernel did not properly handle invalid IP options in some situations. An

attacker could use this to cause a denial of service or possibly execute

...

Read the Full Advisory

Topics Covered

security advisory security issue critical Ubuntu kernel Denial of Service system crash

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1012-gke      4.4.0-1012.12
  linux-image-4.4.0-1016-aws      4.4.0-1016.25
  linux-image-4.4.0-1054-raspi2   4.4.0-1054.61
  linux-image-4.4.0-1057-snapdragon  4.4.0-1057.61
  linux-image-4.4.0-75-generic    4.4.0-75.96
  linux-image-4.4.0-75-generic-lpae  4.4.0-75.96
  linux-image-4.4.0-75-lowlatency  4.4.0-75.96
  linux-image-4.4.0-75-powerpc-e500mc  4.4.0-75.96
  linux-image-4.4.0-75-powerpc-smp  4.4.0-75.96
  linux-image-4.4.0-75-powerpc64-smp  4.4.0-75.96
  linux-image-aws                 4.4.0.1016.19
  linux-image-generic             4.4.0.75.81
  linux-image-generic-lpae        4.4.0.75.81
  linux-image-gke                 4.4.0.1012.14
  linux-image-lowlatency          4.4.0.75.81
  linux-image-powerpc-e500mc      4.4.0.75.81
  linux-image-powerpc-smp         4.4.0.75.81
  linux-image-powerpc64-smp       4.4.0.75.81
  linux-image-raspi2              4.4.0.1054.55
  linux-image-snapdragon          4.4.0.1057.50

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.