=========================================================================
Ubuntu Security Notice USN-5470-1
June 08, 2022

linux-oem-5.14 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-oem-5.14: Linux kernel for OEM systems

Details:

It was discovered that the Linux kernel did not properly restrict access to
the kernel debugger when booted in secure boot environments. A privileged
attacker could use this to bypass UEFI Secure Boot restrictions.
(CVE-2022-21499)

Aaron Adams discovered that the netfilter subsystem in the Linux kernel did
not properly handle the removal of stateful expressions in some situations,
leading to a use-after-free vulnerability. A local attacker could use this
to cause a denial of service (system crash) or execute arbitrary code.
(CVE-2022-1966)

Minh Yuan discovered that the floppy driver in the Linux kernel contained a
race condition in some situations, 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-2022-1836)

Ziming Zhang discovered that the netfilter subsystem in the Linux kernel
did not properly validate sets with multiple ranged fields. A local
attacker could use this to cause a denial of service or execute arbitrary
code. (CVE-2022-1972)

Update instructions:

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

Ubuntu 20.04 LTS:
  linux-image-5.14.0-1042-oem     5.14.0-1042.47
  linux-image-oem-20.04           5.14.0.1042.38
  linux-image-oem-20.04b          5.14.0.1042.38
  linux-image-oem-20.04c          5.14.0.1042.38
  linux-image-oem-20.04d          5.14.0.1042.38

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.

References:
  https://ubuntu.com/security/notices/USN-5470-1
  CVE-2022-1836, CVE-2022-1966, CVE-2022-1972, CVE-2022-21499

Package Information:
  https://launchpad.net/ubuntu/+source/linux-oem-5.14/5.14.0-1042.47