1. Ubuntu Security Notices
  2. USN-5116-2

USN-5116-2: Linux kernel vulnerabilities

Publication date

22 October 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-aws-5.4 - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-5.4 - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gcp-5.4 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gke - Linux kernel for Google Container Engine (GKE) systems
  • linux-gke-5.4 - Linux kernel for Google Container Engine (GKE) systems
  • linux-gkeop - Linux kernel for Google Container Engine (GKE) systems
  • linux-gkeop-5.4 - Linux kernel for Google Container Engine (GKE) systems
  • linux-ibm - Linux kernel for IBM cloud systems
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-oracle-5.4 - Linux kernel for Oracle Cloud systems
  • linux-raspi - Linux kernel for Raspberry Pi systems
  • linux-raspi-5.4 - Linux kernel for Raspberry Pi systems

Details

It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)

Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)

It was discovered that the KVM hypervisor implementation in the Linux
kernel did not properly compute the access permissions for shadow pages in
some situations. A local attacker could use this to cause a denial of
service. (CVE-2021-38198)

It was discovered that the Xilinx 10/100 Ethernet Lite device driver in the
Linux kernel could report pointer addresses in some situations. An attacker
could use...

It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)

Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)

It was discovered that the KVM hypervisor implementation in the Linux
kernel did not properly compute the access permissions for shadow pages in
some situations. A local attacker could use this to cause a denial of
service. (CVE-2021-38198)

It was discovered that the Xilinx 10/100 Ethernet Lite device driver in the
Linux kernel could report pointer addresses in some situations. An attacker
could use this information to ease the exploitation of another
vulnerability. (CVE-2021-38205)

It was discovered that the ext4 file system in the Linux kernel contained a
race condition when writing xattrs to an inode. A local attacker could use
this to cause a denial of service or possibly gain administrative
privileges. (CVE-2021-40490)

It was discovered that the 6pack network protocol driver in the Linux
kernel did not properly perform validation checks. A privileged attacker
could use this to cause a denial of service (system crash) or execute
arbitrary code. (CVE-2021-42008)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
20.04 focal linux-image-gkeop –  5.4.0.1025.28
linux-image-5.4.0-1058-aws –  5.4.0-1058.61
linux-image-5.4.0-1062-azure –  5.4.0-1062.65
linux-image-ibm –  5.4.0.1006.7
linux-image-5.4.0-1045-raspi –  5.4.0-1045.49
linux-image-5.4.0-1056-gcp –  5.4.0-1056.60
linux-image-5.4.0-1056-oracle –  5.4.0-1056.60
linux-image-5.4.0-1006-ibm –  5.4.0-1006.7
linux-image-ibm-lts-20.04 –  5.4.0.1006.7
linux-image-azure-lts-20.04 –  5.4.0.1062.60
linux-image-gkeop-5.4 –  5.4.0.1025.28
linux-image-gke –  5.4.0.1054.64
linux-image-aws-lts-20.04 –  5.4.0.1058.61
linux-image-raspi2 –  5.4.0.1045.80
linux-image-5.4.0-1025-gkeop –  5.4.0-1025.26
linux-image-gcp-lts-20.04 –  5.4.0.1056.66
linux-image-oracle-lts-20.04 –  5.4.0.1056.56
linux-image-5.4.0-1054-gke –  5.4.0-1054.57
linux-image-raspi –  5.4.0.1045.80
linux-image-gke-5.4 –  5.4.0.1054.64
18.04 bionic linux-image-5.4.0-1058-aws –  5.4.0-1058.61~18.04.3
linux-image-aws –  5.4.0.1058.41
linux-image-raspi-hwe-18.04 –  5.4.0.1045.48
linux-image-5.4.0-1062-azure –  5.4.0-1062.65~18.04.1
linux-image-5.4.0-1056-gcp –  5.4.0-1056.60~18.04.1
linux-image-gkeop-5.4 –  5.4.0.1025.26~18.04.26
linux-image-azure –  5.4.0.1062.42
linux-image-5.4.0-1025-gkeop –  5.4.0-1025.26~18.04.1
linux-image-gcp –  5.4.0.1056.42
linux-image-oracle –  5.4.0.1056.60~18.04.36
linux-image-5.4.0-1054-gke –  5.4.0-1054.57~18.04.1
linux-image-5.4.0-1056-oracle –  5.4.0-1056.60~18.04.1
linux-image-gke-5.4 –  5.4.0.1054.57~18.04.19
linux-image-5.4.0-1045-raspi –  5.4.0-1045.49~18.04.1

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References

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