Ubuntu 21.10 USN-5468-1: Critical Kernel Access Control Issues

ubuntu

June 8, 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-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 systems

- linux-aws-5.13: Linux kernel for Amazon Web Services (AWS) systems

- linux-azure-5.13: Linux kernel for Microsoft Azure cloud systems

- linux-gcp-5.13: Linux kernel for Google Cloud Platform (GCP) systems

- linux-hwe-5.13: Linux hardware enablement (HWE) kernel

- linux-intel-5.13: Linux kernel for Intel IOTG

- linux-oracle-5.13: Linux kernel for Oracle Cloud systems

Details:

It was discovered that the Linux kernel did not properly restrict access to

the kernel debugger when booted in secure boot environments. A privileged

attacker could ...

Read the Full Advisory

Topics Covered

security advisory denial of service critical access control kernel system update ubuntu

Update Instructions

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

Ubuntu 21.10:
  linux-image-5.13.0-1027-kvm     5.13.0-1027.29
  linux-image-5.13.0-1028-aws     5.13.0-1028.31
  linux-image-5.13.0-1028-azure   5.13.0-1028.33
  linux-image-5.13.0-1030-gcp     5.13.0-1030.36
  linux-image-5.13.0-1031-raspi   5.13.0-1031.34
  linux-image-5.13.0-1031-raspi-nolpae  5.13.0-1031.34
  linux-image-5.13.0-1033-oracle  5.13.0-1033.39
  linux-image-5.13.0-48-generic   5.13.0-48.54
  linux-image-5.13.0-48-generic-64k  5.13.0-48.54
  linux-image-5.13.0-48-generic-lpae  5.13.0-48.54
  linux-image-5.13.0-48-lowlatency  5.13.0-48.54
  linux-image-aws                 5.13.0.1028.28
  linux-image-azure               5.13.0.1028.27
  linux-image-gcp                 5.13.0.1030.27
  linux-image-generic             5.13.0.48.56
  linux-image-generic-64k         5.13.0.48.56
  linux-image-generic-lpae        5.13.0.48.56
  linux-image-gke                 5.13.0.1030.27
  linux-image-kvm                 5.13.0.1027.26
  linux-image-lowlatency          5.13.0.48.56
  linux-image-oem-20.04           5.13.0.48.56
  linux-image-oracle              5.13.0.1033.32
  linux-image-raspi               5.13.0.1031.35
  linux-image-raspi-nolpae        5.13.0.1031.35
  linux-image-virtual             5.13.0.48.56

Ubuntu 20.04 LTS:
  linux-image-5.13.0-1014-intel   5.13.0-1014.15
  linux-image-5.13.0-1028-aws     5.13.0-1028.31~20.04.1
  linux-image-5.13.0-1028-azure   5.13.0-1028.33~20.04.1
  linux-image-5.13.0-1030-gcp     5.13.0-1030.36~20.04.1
  linux-image-5.13.0-1033-oracle  5.13.0-1033.39~20.04.1
  linux-image-5.13.0-48-generic   5.13.0-48.54~20.04.1
  linux-image-5.13.0-48-generic-64k  5.13.0-48.54~20.04.1
  linux-image-5.13.0-48-generic-lpae  5.13.0-48.54~20.04.1
  linux-image-5.13.0-48-lowlatency  5.13.0-48.54~20.04.1
  linux-image-aws                 5.13.0.1028.31~20.04.22
  linux-image-azure               5.13.0.1028.33~20.04.17
  linux-image-gcp                 5.13.0.1030.36~20.04.1
  linux-image-generic-64k-hwe-20.04  5.13.0.48.54~20.04.30
  linux-image-generic-hwe-20.04   5.13.0.48.54~20.04.30
  linux-image-generic-lpae-hwe-20.04  5.13.0.48.54~20.04.30
  linux-image-intel               5.13.0.1014.14
  linux-image-lowlatency-hwe-20.04  5.13.0.48.54~20.04.30
  linux-image-oracle              5.13.0.1033.39~20.04.1
  linux-image-virtual-hwe-20.04   5.13.0.48.54~20.04.30

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.