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

USN-5116-1: Linux kernel vulnerabilities

Publication date

20 October 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

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-5.4.0-89-generic –  5.4.0-89.100
linux-image-virtual –  5.4.0.89.93
linux-image-generic –  5.4.0.89.93
linux-image-oem –  5.4.0.89.93
linux-image-5.4.0-1020-bluefield –  5.4.0-1020.23
linux-image-5.4.0-89-generic-lpae –  5.4.0-89.100
linux-image-bluefield –  5.4.0.1020.21
linux-image-oem-osp1 –  5.4.0.89.93
linux-image-5.4.0-1048-kvm –  5.4.0-1048.50
linux-image-5.4.0-89-lowlatency –  5.4.0-89.100
linux-image-kvm –  5.4.0.1048.47
linux-image-generic-lpae –  5.4.0.89.93
linux-image-lowlatency –  5.4.0.89.93
18.04 bionic linux-image-generic-hwe-18.04 –  5.4.0.89.100~18.04.79
linux-image-snapdragon-hwe-18.04 –  5.4.0.89.100~18.04.79
linux-image-5.4.0-89-generic –  5.4.0-89.100~18.04.1
linux-image-oem –  5.4.0.89.100~18.04.79
linux-image-5.4.0-89-generic-lpae –  5.4.0-89.100~18.04.1
linux-image-oem-osp1 –  5.4.0.89.100~18.04.79
linux-image-generic-lpae-hwe-18.04 –  5.4.0.89.100~18.04.79
linux-image-5.4.0-1055-gcp –  5.4.0-1055.59~18.04.1
linux-image-virtual-hwe-18.04 –  5.4.0.89.100~18.04.79
linux-image-gcp –  5.4.0.1055.41
linux-image-5.4.0-89-lowlatency –  5.4.0-89.100~18.04.1
linux-image-lowlatency-hwe-18.04 –  5.4.0.89.100~18.04.79

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References

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