USN-4681-1: Linux kernel vulnerabilities

06 January 2021

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

Ryan Hall discovered that the Intel 700 Series Ethernet Controllers driver
in the Linux kernel did not properly deallocate memory in some conditions.
A local attacker could use this to cause a denial of service (kernel memory
exhaustion). (CVE-2019-0148)

It was discovered that the console keyboard driver in the Linux kernel
contained a race condition. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2020-25656)

Minh Yuan discovered that the tty driver in the Linux kernel contained race
conditions when handling fonts. A local attacker could possibly use this to
expose sensitive information (kernel memory). (CVE-2020-25668)

Jinoh Kang discovered that the Xen event channel infrastructure in the
Linux kernel contained a race condition. An attacker in guest could
possibly use this to cause a denial of service (dom0 crash).
(CVE-2020-27675)

Minh Yuan discovered that the framebuffer console driver in the Linux
kernel did not properly handle fonts in some conditions. A local attacker
could use this to cause a denial of service (system crash) or possibly
expose sensitive information (kernel memory). (CVE-2020-28974)

It was discovered that Power 9 processors could be coerced to expose
information from the L1 cache in certain situations. A local attacker could
use this to expose sensitive information. (CVE-2020-4788)

Update instructions

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

Ubuntu 16.04
Ubuntu 14.04

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.

Related notices

  • USN-4660-1: linux-image-oem, linux-hwe, linux-image-gke, linux-image-powerpc-e500mc, linux-image-4.15.0-1059-oracle, linux-image-lowlatency-hwe-16.04, linux-image-virtual-hwe-16.04, linux-image-4.15.0-1100-azure, linux-image-raspi2, linux-image-azure-lts-18.04, linux-image-gcp-lts-18.04, linux-image-azure-edge, linux-image-generic-lpae, linux-image-aws-hwe, linux-image-4.15.0-1088-gcp, linux-image-generic-lpae-hwe-16.04, linux-image-lowlatency-hwe-16.04-edge, linux-image-powerpc64-emb, linux-kvm, linux-image-virtual-hwe-16.04-edge, linux-image-4.15.0-126-generic-lpae, linux-image-oracle, linux-image-4.15.0-1088-aws, linux-image-4.15.0-1074-gke, linux-azure-4.15, linux-image-generic, linux-image-lowlatency, linux-image-virtual, linux-image-kvm, linux-image-4.15.0-126-generic, linux-oracle, linux-snapdragon, linux-gcp-4.15, linux-image-4.15.0-1074-raspi2, linux-aws-hwe, linux-image-generic-lpae-hwe-16.04-edge, linux-image-powerpc64-smp, linux, linux-image-4.15.0-1091-snapdragon, linux-image-generic-hwe-16.04, linux-image-4.15.0-1103-oem, linux-image-4.15.0-126-lowlatency, linux-image-powerpc-smp, linux-gcp, linux-image-gke-4.15, linux-oem, linux-image-snapdragon, linux-aws, linux-image-azure, linux-raspi2, linux-image-generic-hwe-16.04-edge, linux-gke-4.15, linux-azure, linux-image-aws-lts-18.04, linux-image-oracle-lts-18.04, linux-image-gcp, linux-image-4.15.0-1079-kvm
  • USN-4658-1: linux-image-oem, linux-image-5.4.0-1023-raspi, linux-image-gke, linux-image-aws, linux-image-virtual-hwe-18.04-edge, linux-image-raspi2, linux-image-generic-lpae, linux-oracle, linux-image-5.4.0-1032-azure, linux-image-azure-edge, linux-image-lowlatency-hwe-18.04, linux-image-virtual-hwe-18.04, linux-kvm, linux-image-raspi-hwe-18.04, linux-image-virtual-hwe-20.04, linux-aws-5.4, linux-image-lowlatency-hwe-20.04, linux-image-oracle, linux-raspi-5.4, linux-image-5.4.0-56-generic-lpae, linux-image-5.4.0-1028-kvm, linux-image-5.4.0-56-generic, linux-image-snapdragon-hwe-18.04, linux-image-5.4.0-56-lowlatency, linux-image-lowlatency-hwe-18.04-edge, linux-image-oem-osp1, linux-image-generic, linux-image-lowlatency, linux-image-generic-hwe-18.04-edge, linux-image-virtual, linux-hwe-5.4, linux-image-aws-edge, linux-image-kvm, linux-oracle-5.4, linux-image-generic-lpae-hwe-18.04-edge, linux-gcp-5.4, linux-image-generic-lpae-hwe-20.04, linux-raspi, linux-image-raspi2-hwe-18.04, linux-image-oracle-edge, linux-image-generic-lpae-hwe-18.04, linux-image-generic-hwe-20.04, linux, linux-image-gcp-edge, linux-image-generic-hwe-18.04, linux-image-raspi-hwe-18.04-edge, linux-image-5.4.0-1030-aws, linux-image-raspi2-hwe-18.04-edge, linux-image-5.4.0-1030-oracle, linux-image-5.4.0-1030-gcp, linux-image-raspi, linux-gcp, linux-aws, linux-image-azure, linux-azure, linux-image-snapdragon-hwe-18.04-edge, linux-image-gcp, linux-azure-5.4
  • USN-4751-1: linux-image-raspi-nolpae, linux-image-generic-hwe-20.04-edge, linux-image-gke, linux-image-aws, linux-image-generic-lpae-hwe-20.04-edge, linux-image-5.8.0-44-generic, linux-image-generic-lpae, linux-oracle, linux-kvm, linux-image-virtual-hwe-20.04, linux-image-lowlatency-hwe-20.04, linux-image-oracle, linux-image-generic-64k-hwe-20.04-edge, linux-image-virtual-hwe-20.04-edge, linux-image-generic, linux-image-lowlatency, linux-image-generic-64k, linux-image-virtual, linux-image-5.8.0-44-lowlatency, linux-image-kvm, linux-image-oem-20.04, linux-image-generic-lpae-hwe-20.04, linux-raspi, linux-image-5.8.0-1021-oracle, linux-image-generic-64k-hwe-20.04, linux-image-5.8.0-1016-raspi, linux-image-generic-hwe-20.04, linux, linux-image-5.8.0-1019-kvm, linux-image-5.8.0-1023-azure, linux-hwe-5.8, linux-image-raspi, linux-gcp, linux-image-5.8.0-1024-aws, linux-aws, linux-image-5.8.0-1016-raspi-nolpae, linux-image-azure, linux-image-5.8.0-44-generic-lpae, linux-azure, linux-image-5.8.0-44-generic-64k, linux-image-gcp, linux-image-lowlatency-hwe-20.04-edge, linux-image-5.8.0-1023-gcp
  • USN-4657-1: linux-image-4.4.0-197-powerpc-e500mc, linux-image-4.4.0-197-generic-lpae, linux-image-4.4.0-197-powerpc64-smp, linux-image-generic-lts-vivid, linux-image-generic-lts-wily, linux-image-aws, linux-image-powerpc-e500mc, linux-image-generic-lpae-lts-wily, linux-image-powerpc-e500mc-lts-wily, linux-image-powerpc-smp-lts-xenial, linux-image-powerpc64-smp-lts-vivid, linux-image-raspi2, linux-image-generic-lpae, linux-image-powerpc64-emb, linux-image-4.4.0-197-lowlatency, linux-kvm, linux-image-4.4.0-197-powerpc-smp, linux-image-powerpc64-emb-lts-xenial, linux-image-4.4.0-1118-aws, linux-image-powerpc-smp-lts-vivid, linux-image-powerpc64-emb-lts-utopic, linux-image-powerpc64-smp-lts-xenial, linux-image-virtual-lts-xenial, linux-image-generic, linux-image-generic-lts-utopic, linux-image-lowlatency, linux-image-virtual, linux-image-virtual-lts-utopic, linux-image-lowlatency-lts-utopic, linux-image-kvm, linux-image-powerpc-e500mc-lts-xenial, linux-image-lowlatency-lts-xenial, linux-image-powerpc64-smp-lts-wily, linux-image-powerpc64-emb-lts-vivid, linux-snapdragon, linux-image-4.4.0-1082-aws, linux-image-4.4.0-197-powerpc64-emb, linux, linux-image-lowlatency-lts-wily, linux-image-powerpc64-smp, linux-image-powerpc-smp-lts-utopic, linux-image-powerpc64-smp-lts-utopic, linux-image-powerpc-e500mc-lts-utopic, linux-image-generic-lpae-lts-vivid, linux-image-powerpc64-emb-lts-wily, linux-image-4.4.0-1142-raspi2, linux-image-powerpc-smp, linux-image-lowlatency-lts-vivid, linux-image-generic-lpae-lts-xenial, linux-lts-xenial, linux-image-4.4.0-1146-snapdragon, linux-image-powerpc-e500mc-lts-vivid, linux-image-4.4.0-1084-kvm, linux-image-snapdragon, linux-aws, linux-image-generic-lpae-lts-utopic, linux-image-virtual-lts-wily, linux-raspi2, linux-image-virtual-lts-vivid, linux-image-generic-lts-xenial, linux-image-4.4.0-197-generic, linux-image-powerpc-smp-lts-wily
  • USN-4680-1: linux-image-oem, linux-hwe, linux-image-gke, linux-image-powerpc-e500mc, linux-image-lowlatency-hwe-16.04, linux-image-virtual-hwe-16.04, linux-image-raspi2, linux-image-azure-lts-18.04, linux-image-gcp-lts-18.04, linux-image-azure-edge, linux-image-generic-lpae, linux-image-aws-hwe, linux-image-lowlatency-hwe-16.04-edge, linux-image-generic-lpae-hwe-16.04, linux-image-powerpc64-emb, linux-kvm, linux-oracle, linux-image-4.15.0-1077-raspi2, linux-image-virtual-hwe-16.04-edge, linux-image-oracle, linux-azure-4.15, linux-image-4.15.0-1062-oracle, linux-image-4.15.0-1103-azure, linux-image-generic, linux-image-lowlatency, linux-image-virtual, linux-image-kvm, linux-image-4.15.0-1091-aws, linux-snapdragon, linux-gcp-4.15, linux-aws-hwe, linux-image-generic-lpae-hwe-16.04-edge, linux-image-4.15.0-1094-snapdragon, linux-image-powerpc64-smp, linux, linux-image-generic-hwe-16.04, linux-image-4.15.0-1077-gke, linux-image-4.15.0-1091-gcp, linux-image-powerpc-smp, linux-image-4.15.0-129-generic, linux-gcp, linux-image-gke-4.15, linux-image-snapdragon, linux-aws, linux-image-azure, linux-raspi2, linux-image-generic-hwe-16.04-edge, linux-gke-4.15, linux-azure, linux-image-4.15.0-1082-kvm, linux-image-aws-lts-18.04, linux-image-4.15.0-129-lowlatency, linux-image-gcp, linux-image-oracle-lts-18.04, linux-image-4.15.0-129-generic-lpae
  • USN-4679-1: linux-image-oem, linux-gke-5.4, linux-image-5.4.0-1034-oracle, linux-image-aws, linux-image-virtual-hwe-18.04-edge, linux-image-5.4.0-1033-gcp, linux-image-raspi2, linux-image-generic-lpae, linux-oracle, linux-image-azure-edge, linux-image-lowlatency-hwe-18.04, linux-image-virtual-hwe-18.04, linux-kvm, linux-image-raspi-hwe-18.04, linux-image-virtual-hwe-20.04, linux-aws-5.4, linux-image-lowlatency-hwe-20.04, linux-image-oracle, linux-raspi-5.4, linux-image-gke-5.4, linux-image-snapdragon-hwe-18.04, linux-image-5.4.0-1034-aws, linux-image-lowlatency-hwe-18.04-edge, linux-image-oem-osp1, linux-image-generic, linux-image-lowlatency, linux-image-generic-hwe-18.04-edge, linux-image-virtual, linux-hwe-5.4, linux-image-aws-edge, linux-image-kvm, linux-image-5.4.0-59-lowlatency, linux-oracle-5.4, linux-image-generic-lpae-hwe-18.04-edge, linux-gcp-5.4, linux-image-generic-lpae-hwe-20.04, linux-raspi, linux-image-raspi2-hwe-18.04, linux-image-oracle-edge, linux-image-generic-lpae-hwe-18.04, linux-image-5.4.0-1031-kvm, linux-image-5.4.0-59-generic-lpae, linux-image-generic-hwe-20.04, linux, linux-image-gcp-edge, linux-image-generic-hwe-18.04, linux-image-raspi-hwe-18.04-edge, linux-image-raspi2-hwe-18.04-edge, linux-image-5.4.0-1035-azure, linux-image-raspi, linux-gcp, linux-aws, linux-image-5.4.0-59-generic, linux-image-azure, linux-image-5.4.0-1033-gke, linux-azure, linux-image-snapdragon-hwe-18.04-edge, linux-image-5.4.0-1026-raspi, linux-image-gcp, linux-azure-5.4
  • USN-4659-1: linux-image-raspi-nolpae, linux-image-generic-hwe-20.04-edge, linux-image-gke, linux-image-aws, linux-image-generic-lpae-hwe-20.04-edge, linux-image-5.8.0-31-generic, linux-image-generic-lpae, linux-oracle, linux-kvm, linux-image-5.8.0-1012-gcp, linux-image-5.8.0-31-generic-lpae, linux-image-virtual-hwe-20.04, linux-image-lowlatency-hwe-20.04, linux-image-5.8.0-1008-raspi, linux-image-oracle, linux-image-5.8.0-1008-raspi-nolpae, linux-image-5.8.0-1011-kvm, linux-image-generic-64k-hwe-20.04-edge, linux-image-virtual-hwe-20.04-edge, linux-image-generic, linux-image-lowlatency, linux-image-generic-64k, linux-image-virtual, linux-image-kvm, linux-image-oem-20.04, linux-image-generic-lpae-hwe-20.04, linux-raspi, linux-image-generic-64k-hwe-20.04, linux-image-5.8.0-1013-azure, linux-image-generic-hwe-20.04, linux, linux-image-5.8.0-31-generic-64k, linux-image-5.8.0-1011-oracle, linux-image-raspi, linux-gcp, linux-aws, linux-image-azure, linux-image-5.8.0-1014-aws, linux-azure, linux-image-gcp, linux-image-lowlatency-hwe-20.04-edge, linux-image-5.8.0-31-lowlatency
  • USN-4683-1: linux-image-oem-20.04, linux-image-5.6.0-1039-oem, linux-oem-5.6