A Linux kernel (OEM) security update has been released for Ubuntu 20.04 LTS.

USN-5789-1: Linux kernel (OEM) vulnerabilities

==========================================================================
Ubuntu Security Notice USN-5789-1
January 05, 2023

linux-oem-5.14 vulnerabilities
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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 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)

Jann Horn discovered that the Linux kernel did not properly track memory
allocations for anonymous VMA mappings in some situations, leading to
potential data structure reuse. A local attacker could use this to cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2022-42703)

Roger Pau Monné discovered that the Xen virtual block driver in the Linux
kernel did not properly initialize memory pages to be used for shared
communication with the backend. A local attacker could use this to expose
sensitive information (guest kernel memory). (CVE-2022-26365)

Jan Beulich discovered that the Xen network device frontend driver in the
Linux kernel incorrectly handled socket buffers (skb) references when
communicating with certain backends. A local attacker could use this to
cause a denial of service (guest crash). (CVE-2022-33743)

It was discovered that a memory leak existed in the IPv6 implementation of
the Linux kernel. A local attacker could use this to cause a denial of
service (memory exhaustion). (CVE-2022-3524)

It was discovered that a race condition existed in the Bluetooth subsystem
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-2022-3564)

It was discovered that the TCP implementation in the Linux kernel contained
a data race condition. An attacker could possibly use this to cause
undesired behaviors. (CVE-2022-3566)

It was discovered that the IPv6 implementation in the Linux kernel
contained a data race condition. An attacker could possibly use this to
cause undesired behaviors. (CVE-2022-3567)

It was discovered that the Realtek RTL8152 USB Ethernet adapter driver in
the Linux kernel did not properly handle certain error conditions. A local
attacker with physical access could plug in a specially crafted USB device
to cause a denial of service (memory exhaustion). (CVE-2022-3594)

It was discovered that a null pointer dereference existed in the NILFS2
file system implementation in the Linux kernel. A local attacker could use
this to cause a denial of service (system crash). (CVE-2022-3621)

Update instructions:

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

Ubuntu 20.04 LTS:
linux-image-5.14.0-1055-oem 5.14.0-1055.62
linux-image-oem-20.04 5.14.0.1055.53
linux-image-oem-20.04b 5.14.0.1055.53
linux-image-oem-20.04c 5.14.0.1055.53
linux-image-oem-20.04d 5.14.0.1055.53

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-5789-1
CVE-2022-26365, CVE-2022-33743, CVE-2022-3524, CVE-2022-3564,
CVE-2022-3566, CVE-2022-3567, CVE-2022-3594, CVE-2022-3621,
CVE-2022-42703, CVE-2022-43945

Package Information:
https://launchpad.net/ubuntu/+source/linux-oem-5.14/5.14.0-1055.62