USN-5361-1: Linux kernel vulnerabilities

1 April 2022

Several security issues were fixed in the Linux kernel.

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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 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)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 16.04
Ubuntu 14.04

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.