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Ubuntu Security Notice USN-5756-3
December 12, 2022

linux-azure, linux-azure-5.4 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-azure-5.4: Linux kernel for Microsoft Azure cloud systems

Details:

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)

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 ISDN implementation of the Linux kernel
contained a use-after-free vulnerability. A privileged user could use this
to cause a denial of service (system crash) or possibly execute arbitrary
code. (CVE-2022-3565)

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-5.4.0-1098-azure    5.4.0-1098.104
   linux-image-azure-lts-20.04     5.4.0.1098.92

Ubuntu 18.04 LTS:
   linux-image-5.4.0-1098-azure    5.4.0-1098.104~18.04.2
   linux-image-azure               5.4.0.1098.72

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-5756-3
   https://ubuntu.com/security/notices/USN-5756-1
   CVE-2022-3524, CVE-2022-3564, CVE-2022-3565, CVE-2022-3566,
   CVE-2022-3567, CVE-2022-3594, CVE-2022-3621, CVE-2022-42703

Package Information:
   https://launchpad.net/ubuntu/+source/linux-azure/5.4.0-1098.104
   https://launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1098.104~18.04.2