USN-4626-1: Linux kernel vulnerabilities

Releases

• Ubuntu 20.10

Packages

• 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

• CVE-2020-8694
• CVE-2020-27194

Related notices

• USN-4627-1: linux-image-lowlatency-pae, linux-image-generic-lpae-hwe-20.04, linux-image-3.13.0-183-powerpc64-smp, linux-gke-5.3, linux-image-lowlatency-hwe-18.04, linux-image-virtual-hwe-18.04, linux-image-generic-lpae-hwe-18.04-edge, linux-image-powerpc-smp-lts-utopic, linux-gcp-5.4, linux-image-3.13.0-183-generic-lpae, linux-image-5.4.0-1029-oracle, linux-image-virtual-hwe-18.04-edge, linux-image-4.15.0-1087-gcp, linux-image-lowlatency-hwe-16.04-edge, linux-image-virtual-lts-vivid, linux-image-generic-hwe-18.04-edge, linux-image-generic-lts-trusty, linux-image-powerpc64-emb-lts-vivid, linux-image-virtual-lts-wily, linux-image-5.3.0-69-lowlatency, linux-image-4.4.0-194-powerpc-e500mc, linux-image-generic-pae, linux-gke-4.15, linux-image-generic-lts-wily, linux-image-generic-lts-quantal, linux-image-highbank, linux-image-virtual, linux-image-virtual-hwe-16.04, linux-image-4.15.0-1073-gke, linux-image-4.4.0-194-generic, linux-image-powerpc64-emb, linux-image-powerpc64-smp-lts-utopic, linux-gcp-4.15, linux-image-4.15.0-1058-oracle, linux-image-5.3.0-69-generic, linux-image-gke, linux-image-server, linux-image-generic-hwe-18.04, linux-image-gcp-edge, linux-image-virtual-lts-utopic, linux-image-3.13.0-183-generic, linux-image-powerpc-e500mc-lts-utopic, linux-image-virtual-hwe-20.04, linux-image-generic-lts-raring, linux-image-generic-lpae-lts-xenial, linux-oem-osp1, linux-image-virtual-lts-xenial, linux-oracle-5.4, linux-image-4.15.0-123-generic-lpae, linux-image-4.4.0-194-generic-lpae, linux-image-3.13.0-183-lowlatency, linux-image-oracle-edge, linux-image-5.0.0-1071-oem-osp1, linux-image-gcp, linux-image-4.4.0-194-powerpc64-smp, linux-image-4.4.0-194-powerpc-smp, linux-image-5.4.0-53-generic, linux-image-lowlatency-hwe-16.04, linux-image-powerpc64-smp-lts-wily, linux-image-powerpc64-smp-lts-xenial, linux-hwe-5.4, linux-image-4.15.0-123-generic, linux-image-3.13.0-183-powerpc-e500, linux-image-gkeop-5.3, linux-image-powerpc-smp-lts-wily, linux-image-5.4.0-53-lowlatency, linux-image-generic-hwe-16.04, linux-image-5.4.0-1029-gcp, linux-image-oem, linux-image-generic-lpae-hwe-16.04-edge, linux-image-powerpc-smp, linux-image-lowlatency, linux-image-5.4.0-53-generic-lpae, linux-image-generic-lpae-lts-utopic, linux-image-3.13.0-183-powerpc64-emb, linux-image-powerpc64-smp-lts-vivid, linux-image-generic-lts-saucy, linux-oem, linux-image-3.13.0-183-powerpc-smp, linux-image-4.15.0-1101-oem, linux-image-generic-lts-xenial, linux-image-powerpc64-smp, linux-image-virtual-hwe-16.04-edge, linux-image-generic-lpae-lts-wily, linux-image-generic, linux-image-generic-lts-vivid, linux-image-oracle, linux-image-powerpc-e500mc-lts-vivid, linux-image-4.4.0-194-powerpc64-emb, linux-image-snapdragon-hwe-18.04, linux-image-oem-osp1, linux-image-3.13.0-183-powerpc-e500mc, linux-image-omap, linux-image-4.15.0-123-lowlatency, linux-image-powerpc-e500mc, linux-image-lowlatency-lts-vivid, linux-image-generic-lpae-hwe-18.04, linux-image-powerpc-e500mc-lts-xenial, linux-image-generic-lpae-lts-vivid, linux-image-4.4.0-194-lowlatency, linux-image-powerpc-e500, linux-image-lowlatency-lts-wily, linux-oracle, linux-image-lowlatency-lts-xenial, linux-image-powerpc-e500mc-lts-wily, linux-image-generic-lpae, linux-image-generic-lpae-lts-saucy, linux-image-generic-lpae-hwe-16.04, linux-image-generic-lpae-lts-trusty, linux-image-5.3.0-1039-gke, linux-image-powerpc64-emb-lts-utopic, linux-image-oracle-lts-18.04, linux-image-powerpc64-emb-lts-xenial, linux-lts-xenial, linux-image-gke-4.15, linux-image-powerpc64-emb-lts-wily, linux-image-gke-5.3, linux-image-gcp-lts-18.04, linux-image-generic-hwe-20.04, linux-image-lowlatency-lts-utopic, linux-image-snapdragon-hwe-18.04-edge, linux-gcp, linux-image-generic-lts-utopic, linux-hwe, linux, linux-image-lowlatency-hwe-20.04, linux-image-powerpc-smp-lts-vivid, linux-lts-trusty, linux-image-powerpc-smp-lts-xenial, linux-image-generic-hwe-16.04-edge, linux-image-lowlatency-hwe-18.04-edge