A Linux kernel security update has been released for Ubuntu Linux 20.10.

USN-4626-1: Linux kernel vulnerabilities

=========================================================================
Ubuntu Security Notice USN-4626-1
November 11, 2020

linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oracle,
linux-raspi vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.10

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-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-kvm: Linux kernel for cloud environments
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-raspi: Linux kernel for Raspberry Pi (V8) systems

Details:

Simon Scannell discovered that the bpf verifier in the Linux kernel did not
properly calculate register bounds for certain operations. A local attacker
could use this to expose sensitive information (kernel memory) or gain
administrative privileges. (CVE-2020-27194)

Moritz Lipp, Michael Schwarz, Andreas Kogler, David Oswald, Catherine
Easdon, Claudio Canella, and Daniel Gruss discovered that the Intel Running
Average Power Limit (RAPL) driver in the Linux kernel did not properly
restrict access to power data. A local attacker could possibly use this to
expose sensitive information. (CVE-2020-8694)

Update instructions:

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

Ubuntu 20.10:
linux-image-5.8.0-1007-raspi 5.8.0-1007.10
linux-image-5.8.0-1007-raspi-nolpae 5.8.0-1007.10
linux-image-5.8.0-1009-kvm 5.8.0-1009.10
linux-image-5.8.0-1010-oracle 5.8.0-1010.10
linux-image-5.8.0-1011-gcp 5.8.0-1011.11
linux-image-5.8.0-1012-azure 5.8.0-1012.13
linux-image-5.8.0-1013-aws 5.8.0-1013.14
linux-image-5.8.0-28-generic 5.8.0-28.30
linux-image-5.8.0-28-generic-64k 5.8.0-28.30
linux-image-5.8.0-28-generic-lpae 5.8.0-28.30
linux-image-5.8.0-28-lowlatency 5.8.0-28.30
linux-image-aws 5.8.0.1013.15
linux-image-azure 5.8.0.1012.12
linux-image-gcp 5.8.0.1011.11
linux-image-generic 5.8.0.28.33
linux-image-generic-64k 5.8.0.28.33
linux-image-generic-lpae 5.8.0.28.33
linux-image-gke 5.8.0.1011.11
linux-image-kvm 5.8.0.1009.10
linux-image-lowlatency 5.8.0.28.33
linux-image-oem-20.04 5.8.0.28.33
linux-image-oracle 5.8.0.1010.10
linux-image-raspi 5.8.0.1007.10
linux-image-raspi-nolpae 5.8.0.1007.10
linux-image-virtual 5.8.0.28.33

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/4626-1
CVE-2020-27194, CVE-2020-8694

Package Information:
  https://launchpad.net/ubuntu/+source/linux/5.8.0-28.30
  https://launchpad.net/ubuntu/+source/linux-aws/5.8.0-1013.14
  https://launchpad.net/ubuntu/+source/linux-azure/5.8.0-1012.13
  https://launchpad.net/ubuntu/+source/linux-gcp/5.8.0-1011.11
  https://launchpad.net/ubuntu/+source/linux-kvm/5.8.0-1009.10
  https://launchpad.net/ubuntu/+source/linux-oracle/5.8.0-1010.10
  https://launchpad.net/ubuntu/+source/linux-raspi/5.8.0-1007.10