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Ubuntu Security Notice USN-6572-1
January 09, 2024

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

- Ubuntu 23.10

Summary:

Several security issues were fixed in the Linux kernel.

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

Details:

Yu Hao discovered that the UBI driver in the Linux kernel did not properly
check for MTD with zero erasesize during device attachment. A local
privileged attacker could use this to cause a denial of service (system
crash). (CVE-2023-31085)

Bien Pham discovered that the netfiler subsystem in the Linux kernel
contained a race condition, leading to a use-after-free vulnerability. A
local user could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2023-4244)

Maxim Levitsky discovered that the KVM nested virtualization (SVM)
implementation for AMD processors in the Linux kernel did not properly
handle x2AVIC MSRs. An attacker in a guest VM could use this to cause a
denial of service (host kernel crash). (CVE-2023-5090)

It was discovered that the SMB network file sharing protocol implementation
in the Linux kernel did not properly handle certain error conditions,
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-2023-5345)

Murray McAllister discovered that the VMware Virtual GPU DRM driver in the
Linux kernel did not properly handle memory objects when storing surfaces,
leading to a use-after-free vulnerability. A local attacker in a guest VM
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2023-5633)

Update instructions:

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

Ubuntu 23.10:
   linux-image-6.5.0-1009-azure    6.5.0-1009.9
   linux-image-6.5.0-1009-azure-fde  6.5.0-1009.9
   linux-image-azure               6.5.0.1009.11
   linux-image-azure-fde           6.5.0.1009.11

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-6572-1
   CVE-2023-31085, CVE-2023-4244, CVE-2023-5090, CVE-2023-5345,
   CVE-2023-5633

Package Information:
   https://launchpad.net/ubuntu/+source/linux-azure/6.5.0-1009.9