Ubuntu 18.04 LTS: USN-5727-1 Critical Denial Of Service Risks

ubuntu

November 16, 2022

Several security issues were fixed in the Linux kernel.

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-dell300x: Linux kernel for Dell 300x platforms

- linux-kvm: Linux kernel for cloud environments

- linux-oracle: Linux kernel for Oracle Cloud systems

- linux-raspi2: Linux kernel for Raspberry Pi systems

- linux-snapdragon: Linux kernel for Qualcomm Snapdragon processors- linux-aws-hwe: Linux kernel for Amazon Web Services (AWS-HWE) systems

- linux-hwe: Linux hardware enablement (HWE) kernel

Details:

It was discovered that a race condition existed in the instruction emulator

of the Linux kernel on Arm 64-bit systems. A local attacker could use this

to cause a denial of service (system crash). (CVE-2022-20422)

It was discovered that the KVM implementation in the Linux kernel did not

properly handle virtual CPUs without APICs in certain situations. A local

attacker could possibly use this to cause a denial of s...

Read the Full Advisory

Topics Covered

security advisory denial of service critical issue software update Ubuntu kernel system crash

Update Instructions

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

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1055-dell300x  4.15.0-1055.60
  linux-image-4.15.0-1108-oracle  4.15.0-1108.119
  linux-image-4.15.0-1121-raspi2  4.15.0-1121.129
  linux-image-4.15.0-1129-kvm     4.15.0-1129.134
  linux-image-4.15.0-1139-snapdragon  4.15.0-1139.149
  linux-image-4.15.0-1143-aws     4.15.0-1143.155
  linux-image-4.15.0-197-generic  4.15.0-197.208
  linux-image-4.15.0-197-generic-lpae  4.15.0-197.208
  linux-image-4.15.0-197-lowlatency  4.15.0-197.208
  linux-image-aws-lts-18.04       4.15.0.1143.143
  linux-image-dell300x            4.15.0.1055.55
  linux-image-generic             4.15.0.197.182
  linux-image-generic-lpae        4.15.0.197.182
  linux-image-kvm                 4.15.0.1129.122
  linux-image-lowlatency          4.15.0.197.182
  linux-image-oracle-lts-18.04    4.15.0.1108.115
  linux-image-raspi2              4.15.0.1121.118
  linux-image-snapdragon          4.15.0.1139.140
  linux-image-virtual             4.15.0.197.182

Ubuntu 16.04 ESM:
  linux-image-4.15.0-1108-oracle  4.15.0-1108.119~16.04.1
  linux-image-4.15.0-1143-aws-hwe  4.15.0-1143.155~16.04.1
  linux-image-4.15.0-197-generic  4.15.0-197.208~16.04.1
  linux-image-4.15.0-197-lowlatency  4.15.0-197.208~16.04.1
  linux-image-aws-hwe             4.15.0.1143.130
  linux-image-generic-hwe-16.04   4.15.0.197.184
  linux-image-lowlatency-hwe-16.04  4.15.0.197.184
  linux-image-oem                 4.15.0.197.184
  linux-image-oracle              4.15.0.1108.92
  linux-image-virtual-hwe-16.04   4.15.0.197.184

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.