A Linux kernel security update has been released for Ubuntu 14.04 ESM and 18.04 LTS.

USN-4713-2: Linux kernel vulnerability

=========================================================================
Ubuntu Security Notice USN-4713-2
February 10, 2021

linux, linux-gke-5.0, linux-gke-5.3, linux-hwe, linux-raspi2-5.3
vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 14.04 ESM

Summary:

The system could allow unintended access to data in some environments.

Software Description:
- linux-gke-5.0: Linux kernel for Google Container Engine (GKE) systems
- linux-gke-5.3: Linux kernel for Google Container Engine (GKE) systems
- linux-hwe: Linux hardware enablement (HWE) kernel
- linux-raspi2-5.3: Linux kernel for Raspberry Pi (V8) systems
- linux: Linux kernel

Details:

It was discovered that the LIO SCSI target implementation in the Linux
kernel performed insufficient identifier checking in certain XCOPY
requests. An attacker with access to at least one LUN in a multiple
backstore environment could use this to expose sensitive information or
modify data.

Update instructions:

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

Ubuntu 18.04 LTS:
linux-image-5.0.0-1051-gke 5.0.0-1051.53
linux-image-5.3.0-1037-raspi2 5.3.0-1037.39
linux-image-5.3.0-1040-gke 5.3.0-1040.43
linux-image-5.3.0-70-generic 5.3.0-70.66
linux-image-5.3.0-70-lowlatency 5.3.0-70.66
linux-image-gke-5.0 5.0.0.1051.35
linux-image-gke-5.3 5.3.0.1040.23
linux-image-gkeop-5.3 5.3.0.70.127
linux-image-raspi2-hwe-18.04 5.3.0.1037.26

Ubuntu 14.04 ESM:
linux-image-3.13.0-184-generic 3.13.0-184.235
linux-image-3.13.0-184-generic-lpae 3.13.0-184.235
linux-image-3.13.0-184-lowlatency 3.13.0-184.235
linux-image-3.13.0-184-powerpc-e500 3.13.0-184.235
linux-image-3.13.0-184-powerpc-e500mc 3.13.0-184.235
linux-image-3.13.0-184-powerpc-smp 3.13.0-184.235
linux-image-3.13.0-184-powerpc64-emb 3.13.0-184.235
linux-image-3.13.0-184-powerpc64-smp 3.13.0-184.235
linux-image-generic 3.13.0.184.193
linux-image-generic-lpae 3.13.0.184.193
linux-image-generic-pae 3.13.0.184.193
linux-image-highbank 3.13.0.184.193
linux-image-lowlatency 3.13.0.184.193
linux-image-lowlatency-pae 3.13.0.184.193
linux-image-omap 3.13.0.184.193
linux-image-powerpc-e500 3.13.0.184.193
linux-image-powerpc-e500mc 3.13.0.184.193
linux-image-powerpc-smp 3.13.0.184.193
linux-image-powerpc64-emb 3.13.0.184.193
linux-image-powerpc64-smp 3.13.0.184.193
linux-image-server 3.13.0.184.193
linux-image-virtual 3.13.0.184.193

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:
  https://usn.ubuntu.com/4713-2
  https://usn.ubuntu.com/4713-1
CVE-2020-28374

Package Information:
  https://launchpad.net/ubuntu/+source/linux-gke-5.0/5.0.0-1051.53
  https://launchpad.net/ubuntu/+source/linux-gke-5.3/5.3.0-1040.43
  https://launchpad.net/ubuntu/+source/linux-hwe/5.3.0-70.66
  https://launchpad.net/ubuntu/+source/linux-raspi2-5.3/5.3.0-1037.39