Ubuntu 18.04: USN-5094-1 Moderate: Kernel Security Flaws Summary

ubuntu

September 29, 2021

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-azure-4.15: Linux kernel for Microsoft Azure Cloud systems

- linux-dell300x: Linux kernel for Dell 300x platforms

- linux-gcp-4.15: Linux kernel for Google Cloud Platform (GCP) systems

- linux-kvm: Linux kernel for cloud environments

- linux-oracle: Linux kernel for Oracle Cloud systems

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

- linux-azure: Linux kernel for Microsoft Azure Cloud systems

- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems

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

Details:

It was discovered that the KVM hypervisor implementation in the Linux

kernel did not properly perform reference counting in some situations,

leading to a use-after-free vulnerability. An attacker who could...

Read the Full Advisory

Topics Covered

security advisory moderate DoS Ubuntu kernel system update information exposure

Update Instructions

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

Ubuntu 18.04 LTS:
  linux-image-4.15.0-1028-dell300x  4.15.0-1028.33
  linux-image-4.15.0-1081-oracle  4.15.0-1081.89
  linux-image-4.15.0-1100-kvm     4.15.0-1100.102
  linux-image-4.15.0-1109-gcp     4.15.0-1109.123
  linux-image-4.15.0-1112-aws     4.15.0-1112.119
  linux-image-4.15.0-1113-snapdragon  4.15.0-1113.122
  linux-image-4.15.0-1124-azure   4.15.0-1124.137
  linux-image-4.15.0-159-generic  4.15.0-159.167
  linux-image-4.15.0-159-generic-lpae  4.15.0-159.167
  linux-image-4.15.0-159-lowlatency  4.15.0-159.167
  linux-image-aws-lts-18.04       4.15.0.1112.115
  linux-image-azure-lts-18.04     4.15.0.1124.97
  linux-image-dell300x            4.15.0.1028.30
  linux-image-gcp-lts-18.04       4.15.0.1109.128
  linux-image-generic             4.15.0.159.148
  linux-image-generic-lpae        4.15.0.159.148
  linux-image-kvm                 4.15.0.1100.96
  linux-image-lowlatency          4.15.0.159.148
  linux-image-oracle-lts-18.04    4.15.0.1081.91
  linux-image-snapdragon          4.15.0.1113.116
  linux-image-virtual             4.15.0.159.148

Ubuntu 16.04 ESM:
  linux-image-4.15.0-1081-oracle  4.15.0-1081.89~16.04.1
  linux-image-4.15.0-1109-gcp     4.15.0-1109.123~16.04.1
  linux-image-4.15.0-1112-aws     4.15.0-1112.119~16.04.1
  linux-image-4.15.0-1124-azure   4.15.0-1124.137~16.04.1
  linux-image-4.15.0-159-generic  4.15.0-159.167~16.04.1
  linux-image-4.15.0-159-lowlatency  4.15.0-159.167~16.04.1
  linux-image-aws-hwe             4.15.0.1112.103
  linux-image-azure               4.15.0.1124.115
  linux-image-gcp                 4.15.0.1109.110
  linux-image-generic-hwe-16.04   4.15.0.159.152
  linux-image-gke                 4.15.0.1109.110
  linux-image-lowlatency-hwe-16.04  4.15.0.159.152
  linux-image-oem                 4.15.0.159.152
  linux-image-oracle              4.15.0.1081.69
  linux-image-virtual-hwe-16.04   4.15.0.159.152

Ubuntu 14.04 ESM:
  linux-image-4.15.0-1124-azure   4.15.0-1124.137~14.04.1
  linux-image-azure               4.15.0.1124.97

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.