==========================================================================
Ubuntu Security Notice USN-6383-1
September 19, 2023

linux, linux-aws, linux-aws-6.2, linux-azure, linux-azure-6.2,
linux-azure-fde-6.2, linux-gcp, linux-gcp-6.2, linux-hwe-6.2, linux-ibm,
linux-kvm, linux-lowlatency, linux-lowlatency-hwe-6.2, linux-oracle,
linux-raspi, linux-starfive vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 23.04
- Ubuntu 22.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux: Linux kernel
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-ibm: Linux kernel for IBM cloud systems
- linux-kvm: Linux kernel for cloud environments
- linux-lowlatency: Linux low latency kernel
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-raspi: Linux kernel for Raspberry Pi systems
- linux-starfive: Linux kernel for StarFive processors
- linux-aws-6.2: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure-6.2: Linux kernel for Microsoft Azure cloud systems
- linux-azure-fde-6.2: Linux kernel for Microsoft Azure CVM cloud systems
- linux-gcp-6.2: Linux kernel for Google Cloud Platform (GCP) systems
- linux-hwe-6.2: Linux hardware enablement (HWE) kernel
- linux-lowlatency-hwe-6.2: Linux low latency kernel

Details:

Jana Hofmann, Emanuele Vannacci, Cedric Fournet, Boris Kopf, and Oleksii
Oleksenko discovered that some AMD processors could leak stale data from
division operations in certain situations. A local attacker could possibly
use this to expose sensitive information. (CVE-2023-20588)

It was discovered that the ARM64 KVM implementation in the Linux kernel did
not properly restrict hypervisor memory access. An attacker in a guest VM
could use this to execute arbitrary code in the host OS. (CVE-2023-21264)

It was discovered that the bluetooth subsystem in the Linux kernel did not
properly handle L2CAP socket release, 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-2023-40283)

It was discovered that some network classifier implementations in the Linux
kernel contained use-after-free vulnerabilities. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2023-4128)

Lonial Con discovered that the netfilter subsystem in the Linux kernel
contained a memory leak when handling certain element flush operations. A
local attacker could use this to expose sensitive information (kernel
memory). (CVE-2023-4569)

Update instructions:

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

Ubuntu 23.04:
   linux-image-6.2.0-1005-starfive  6.2.0-1005.6
   linux-image-6.2.0-1010-ibm      6.2.0-1010.10
   linux-image-6.2.0-1012-aws      6.2.0-1012.12
   linux-image-6.2.0-1012-azure    6.2.0-1012.12
   linux-image-6.2.0-1012-oracle   6.2.0-1012.12
   linux-image-6.2.0-1013-kvm      6.2.0-1013.13
   linux-image-6.2.0-1013-lowlatency  6.2.0-1013.13
   linux-image-6.2.0-1013-lowlatency-64k  6.2.0-1013.13
   linux-image-6.2.0-1013-raspi    6.2.0-1013.15
   linux-image-6.2.0-1014-gcp      6.2.0-1014.14
   linux-image-6.2.0-33-generic    6.2.0-33.33+1
   linux-image-6.2.0-33-generic-64k  6.2.0-33.33+1
   linux-image-6.2.0-33-generic-lpae  6.2.0-33.33
   linux-image-aws                 6.2.0.1012.13
   linux-image-azure               6.2.0.1012.12
   linux-image-gcp                 6.2.0.1014.14
   linux-image-generic             6.2.0.33.33
   linux-image-generic-64k         6.2.0.33.33
   linux-image-generic-lpae        6.2.0.33.33
   linux-image-ibm                 6.2.0.1010.10
   linux-image-kvm                 6.2.0.1013.13
   linux-image-lowlatency          6.2.0.1013.13
   linux-image-lowlatency-64k      6.2.0.1013.13
   linux-image-oracle              6.2.0.1012.12
   linux-image-raspi               6.2.0.1013.16
   linux-image-raspi-nolpae        6.2.0.1013.16
   linux-image-starfive            6.2.0.1005.8
   linux-image-virtual             6.2.0.33.33

Ubuntu 22.04 LTS:
   linux-image-6.2.0-1012-aws      6.2.0-1012.12~22.04.1
   linux-image-6.2.0-1012-azure    6.2.0-1012.12~22.04.1
   linux-image-6.2.0-1012-azure-fde  6.2.0-1012.12~22.04.1.1
   linux-image-6.2.0-1013-lowlatency  6.2.0-1013.13~22.04.1
   linux-image-6.2.0-1013-lowlatency-64k  6.2.0-1013.13~22.04.1
   linux-image-6.2.0-1014-gcp      6.2.0-1014.14~22.04.1
   linux-image-6.2.0-33-generic    6.2.0-33.33~22.04.1
   linux-image-6.2.0-33-generic-64k  6.2.0-33.33~22.04.1
   linux-image-6.2.0-33-generic-lpae  6.2.0-33.33~22.04.1
   linux-image-aws                 6.2.0.1012.12~22.04.1
   linux-image-azure               6.2.0.1012.12~22.04.1
   linux-image-azure-fde           6.2.0.1012.12~22.04.1.9
   linux-image-gcp                 6.2.0.1014.14~22.04.1
   linux-image-generic-64k-hwe-22.04  6.2.0.33.33~22.04.10
   linux-image-generic-hwe-22.04   6.2.0.33.33~22.04.10
   linux-image-generic-lpae-hwe-22.04  6.2.0.33.33~22.04.10
   linux-image-lowlatency-64k-hwe-22.04  6.2.0.1013.13~22.04.10
   linux-image-lowlatency-hwe-22.04  6.2.0.1013.13~22.04.10
   linux-image-virtual-hwe-22.04   6.2.0.33.33~22.04.10

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-6383-1
   CVE-2023-20588, CVE-2023-21264, CVE-2023-40283, CVE-2023-4128,
   CVE-2023-4569

Package Information:
   https://launchpad.net/ubuntu/+source/linux/6.2.0-33.33
   https://launchpad.net/ubuntu/+source/linux-aws/6.2.0-1012.12
   https://launchpad.net/ubuntu/+source/linux-azure/6.2.0-1012.12
   https://launchpad.net/ubuntu/+source/linux-gcp/6.2.0-1014.14
   https://launchpad.net/ubuntu/+source/linux-ibm/6.2.0-1010.10
   https://launchpad.net/ubuntu/+source/linux-kvm/6.2.0-1013.13
   https://launchpad.net/ubuntu/+source/linux-lowlatency/6.2.0-1013.13
   https://launchpad.net/ubuntu/+source/linux-oracle/6.2.0-1012.12
   https://launchpad.net/ubuntu/+source/linux-raspi/6.2.0-1013.15
   https://launchpad.net/ubuntu/+source/linux-starfive/6.2.0-1005.6
   https://launchpad.net/ubuntu/+source/linux-aws-6.2/6.2.0-1012.12~22.04.1
   https://launchpad.net/ubuntu/+source/linux-azure-6.2/6.2.0-1012.12~22.04.1
 
https://launchpad.net/ubuntu/+source/linux-azure-fde-6.2/6.2.0-1012.12~22.04.1.1
   https://launchpad.net/ubuntu/+source/linux-gcp-6.2/6.2.0-1014.14~22.04.1
   https://launchpad.net/ubuntu/+source/linux-hwe-6.2/6.2.0-33.33~22.04.1
 
https://launchpad.net/ubuntu/+source/linux-lowlatency-hwe-6.2/6.2.0-1013.13~22.04.1