USN-5802-1: Linux kernel vulnerabilities

12 January 2023

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 NFSD implementation in the Linux kernel did not
properly handle some RPC messages, leading to a buffer overflow. A remote
attacker could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2022-43945)

Tamás Koczka discovered that the Bluetooth L2CAP handshake implementation
in the Linux kernel contained multiple use-after-free vulnerabilities. A
physically proximate attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2022-42896)

It was discovered that the Xen netback driver in the Linux kernel did not
properly handle packets structured in certain ways. An attacker in a guest
VM could possibly use this to cause a denial of service (host NIC
availability). (CVE-2022-3643)

It was discovered that an integer overflow vulnerability existed in the
Bluetooth subsystem in the Linux kernel. A physically proximate attacker
could use this to cause a denial of service (system crash).
(CVE-2022-45934)

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.