1. Ubuntu Security Notices
  2. USN-5361-1

USN-5361-1: Linux kernel vulnerabilities

Publication date

1 April 2022

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

It was discovered that the VFIO PCI driver in the Linux kernel did not
properly handle attempts to access disabled memory spaces. A local attacker
could use this to cause a denial of service (system crash).
(CVE-2020-12888)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation did
not properly verify certain fragmented frames. A physically proximate
attacker could possibly use this issue to inject or decrypt packets.
(CVE-2020-26141)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation
accepted plaintext fragments in certain situations. A physically proximate
attacker could use this issue to inject packets. (CVE-2020-26145)

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...

It was discovered that the VFIO PCI driver in the Linux kernel did not
properly handle attempts to access disabled memory spaces. A local attacker
could use this to cause a denial of service (system crash).
(CVE-2020-12888)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation did
not properly verify certain fragmented frames. A physically proximate
attacker could possibly use this issue to inject or decrypt packets.
(CVE-2020-26141)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation
accepted plaintext fragments in certain situations. A physically proximate
attacker could use this issue to inject packets. (CVE-2020-26145)

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)

It was discovered a race condition existed in the Unix domain socket
implementation in the Linux kernel, leading to a use-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2021-0920)

It was discovered that the IPv6 implementation in the Linux kernel
contained a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2021-0935)

Zygo Blaxell discovered that the btrfs file system implementation in the
Linux kernel contained a race condition during certain cloning operations.
A local attacker could possibly use this to cause a denial of service
(system crash). (CVE-2021-28964)

Dan Carpenter discovered that the block device manager (dm) implementation
in the Linux kernel contained a buffer overflow in the ioctl for listing
devices. A privileged local attacker could use this to cause a denial of
service (system crash). (CVE-2021-31916)

It was discovered that the Option USB High Speed Mobile device driver in
the Linux kernel did not properly handle error conditions. A physically
proximate attacker could use this to cause a denial of service (system
crash) or possibly execute arbitrary code. (CVE-2021-37159)

It was discovered that the network packet filtering implementation in the
Linux kernel did not properly initialize information in certain
circumstances. A local attacker could use this to expose sensitive
information (kernel memory). (CVE-2021-39636)

Jann Horn discovered a race condition in the Unix domain socket
implementation in the Linux kernel that could result in a read-after-free.
A local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code. (CVE-2021-4083)

Luo Likang discovered that the FireDTV Firewire driver in the Linux kernel
did not properly perform bounds checking in some situations. A local
attacker could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2021-42739)

Brendan Dolan-Gavitt discovered that the Marvell WiFi-Ex USB device driver
in the Linux kernel did not properly handle some error conditions. A
physically proximate attacker could use this to cause a denial of service
(system crash). (CVE-2021-43976)

Amit Klein discovered that the IPv4 implementation in the Linux kernel
could disclose internal state in some situations. An attacker could
possibly use this to expose sensitive information. (CVE-2021-45486)

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
16.04 xenial linux-image-4.4.0-223-lowlatency –  4.4.0-223.256  
linux-image-virtual –  4.4.0.223.230  
linux-image-generic –  4.4.0.223.230  
linux-image-4.4.0-223-generic –  4.4.0-223.256  
linux-image-aws –  4.4.0.1139.144  
linux-image-4.4.0-1104-kvm –  4.4.0-1104.113  
linux-image-kvm –  4.4.0.1104.102  
linux-image-4.4.0-1139-aws –  4.4.0-1139.153  
linux-image-lowlatency –  4.4.0.223.230  
14.04 trusty linux-image-4.4.0-223-generic –  4.4.0-223.256~14.04.1  
linux-image-lowlatency-lts-xenial –  4.4.0.223.194  
linux-image-generic-lts-xenial –  4.4.0.223.194  
linux-image-aws –  4.4.0.1103.101  
linux-image-4.4.0-1103-aws –  4.4.0-1103.108  
linux-image-4.4.0-223-lowlatency –  4.4.0-223.256~14.04.1  
linux-image-virtual-lts-xenial –  4.4.0.223.194  

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References

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