==========================================================================
Ubuntu Security Notice USN-6386-1
September 19, 2023

linux, linux-aws, linux-aws-5.15, linux-azure, linux-azure-5.15,
linux-azure-fde, linux-azure-fde-5.15, linux-gcp, linux-gcp-5.15,
linux-gke, linux-gkeop, linux-gkeop-5.15, linux-hwe-5.15, linux-ibm,
linux-ibm-5.15, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15,
linux-nvidia vulnerabilities
==========================================================================

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

- Ubuntu 22.04 LTS
- Ubuntu 20.04 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-azure-fde: Linux kernel for Microsoft Azure CVM cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-gke: Linux kernel for Google Container Engine (GKE) systems
- linux-gkeop: Linux kernel for Google Container Engine (GKE) systems
- linux-ibm: Linux kernel for IBM cloud systems
- linux-kvm: Linux kernel for cloud environments
- linux-lowlatency: Linux low latency kernel
- linux-nvidia: Linux kernel for NVIDIA systems
- linux-aws-5.15: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure-5.15: Linux kernel for Microsoft Azure cloud systems
- linux-azure-fde-5.15: Linux kernel for Microsoft Azure CVM cloud systems
- linux-gcp-5.15: Linux kernel for Google Cloud Platform (GCP) systems
- linux-gkeop-5.15: Linux kernel for Google Container Engine (GKE) systems
- linux-hwe-5.15: Linux hardware enablement (HWE) kernel
- linux-ibm-5.15: Linux kernel for IBM cloud systems
- linux-lowlatency-hwe-5.15: 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 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 22.04 LTS:
   linux-image-5.15.0-1028-gkeop   5.15.0-1028.33
   linux-image-5.15.0-1033-nvidia  5.15.0-1033.33
   linux-image-5.15.0-1033-nvidia-lowlatency  5.15.0-1033.33
   linux-image-5.15.0-1038-ibm     5.15.0-1038.41
   linux-image-5.15.0-1042-gcp     5.15.0-1042.50
   linux-image-5.15.0-1042-gke     5.15.0-1042.47
   linux-image-5.15.0-1042-kvm     5.15.0-1042.47
   linux-image-5.15.0-1045-aws     5.15.0-1045.50
   linux-image-5.15.0-1047-azure   5.15.0-1047.54
   linux-image-5.15.0-1047-azure-fde  5.15.0-1047.54.1
   linux-image-5.15.0-84-generic   5.15.0-84.93
   linux-image-5.15.0-84-generic-64k  5.15.0-84.93
   linux-image-5.15.0-84-generic-lpae  5.15.0-84.93
   linux-image-5.15.0-84-lowlatency  5.15.0-84.93
   linux-image-5.15.0-84-lowlatency-64k  5.15.0-84.93
   linux-image-aws-lts-22.04       5.15.0.1045.44
   linux-image-azure-fde-lts-22.04  5.15.0.1047.54.25
   linux-image-azure-lts-22.04     5.15.0.1047.43
   linux-image-gcp-lts-22.04       5.15.0.1042.38
   linux-image-generic             5.15.0.84.81
   linux-image-generic-64k         5.15.0.84.81
   linux-image-generic-lpae        5.15.0.84.81
   linux-image-gke                 5.15.0.1042.41
   linux-image-gke-5.15            5.15.0.1042.41
   linux-image-gkeop               5.15.0.1028.27
   linux-image-gkeop-5.15          5.15.0.1028.27
   linux-image-ibm                 5.15.0.1038.34
   linux-image-kvm                 5.15.0.1042.38
   linux-image-lowlatency          5.15.0.84.86
   linux-image-lowlatency-64k      5.15.0.84.86
   linux-image-nvidia              5.15.0.1033.33
   linux-image-nvidia-lowlatency   5.15.0.1033.33
   linux-image-virtual             5.15.0.84.81

Ubuntu 20.04 LTS:
   linux-image-5.15.0-1028-gkeop   5.15.0-1028.33~20.04.1
   linux-image-5.15.0-1038-ibm     5.15.0-1038.41~20.04.1
   linux-image-5.15.0-1042-gcp     5.15.0-1042.50~20.04.1
   linux-image-5.15.0-1045-aws     5.15.0-1045.50~20.04.1
   linux-image-5.15.0-1047-azure   5.15.0-1047.54~20.04.1
   linux-image-5.15.0-1047-azure-fde  5.15.0-1047.54~20.04.1.1
   linux-image-5.15.0-84-generic   5.15.0-84.93~20.04.1
   linux-image-5.15.0-84-generic-64k  5.15.0-84.93~20.04.1
   linux-image-5.15.0-84-generic-lpae  5.15.0-84.93~20.04.1
   linux-image-5.15.0-84-lowlatency  5.15.0-84.93~20.04.1
   linux-image-5.15.0-84-lowlatency-64k  5.15.0-84.93~20.04.1
   linux-image-aws                 5.15.0.1045.50~20.04.33
   linux-image-azure               5.15.0.1047.54~20.04.36
   linux-image-azure-cvm           5.15.0.1047.54~20.04.36
   linux-image-azure-fde           5.15.0.1047.54~20.04.1.25
   linux-image-gcp                 5.15.0.1042.50~20.04.1
   linux-image-generic-64k-hwe-20.04  5.15.0.84.93~20.04.42
   linux-image-generic-hwe-20.04   5.15.0.84.93~20.04.42
   linux-image-generic-lpae-hwe-20.04  5.15.0.84.93~20.04.42
   linux-image-gkeop-5.15          5.15.0.1028.33~20.04.24
   linux-image-ibm                 5.15.0.1038.41~20.04.10
   linux-image-lowlatency-64k-hwe-20.04  5.15.0.84.93~20.04.39
   linux-image-lowlatency-hwe-20.04  5.15.0.84.93~20.04.39
   linux-image-oem-20.04           5.15.0.84.93~20.04.42
   linux-image-oem-20.04b          5.15.0.84.93~20.04.42
   linux-image-oem-20.04c          5.15.0.84.93~20.04.42
   linux-image-oem-20.04d          5.15.0.84.93~20.04.42
   linux-image-virtual-hwe-20.04   5.15.0.84.93~20.04.42

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-6386-1
   CVE-2023-20588, CVE-2023-40283, CVE-2023-4128, CVE-2023-4569

Package Information:
   https://launchpad.net/ubuntu/+source/linux/5.15.0-84.93
   https://launchpad.net/ubuntu/+source/linux-aws/5.15.0-1045.50
   https://launchpad.net/ubuntu/+source/linux-azure/5.15.0-1047.54
   https://launchpad.net/ubuntu/+source/linux-azure-fde/5.15.0-1047.54.1
   https://launchpad.net/ubuntu/+source/linux-gcp/5.15.0-1042.50
   https://launchpad.net/ubuntu/+source/linux-gke/5.15.0-1042.47
   https://launchpad.net/ubuntu/+source/linux-gkeop/5.15.0-1028.33
   https://launchpad.net/ubuntu/+source/linux-ibm/5.15.0-1038.41
   https://launchpad.net/ubuntu/+source/linux-kvm/5.15.0-1042.47
   https://launchpad.net/ubuntu/+source/linux-lowlatency/5.15.0-84.93
   https://launchpad.net/ubuntu/+source/linux-nvidia/5.15.0-1033.33
   https://launchpad.net/ubuntu/+source/linux-aws-5.15/5.15.0-1045.50~20.04.1
   https://launchpad.net/ubuntu/+source/linux-azure-5.15/5.15.0-1047.54~20.04.1
 
https://launchpad.net/ubuntu/+source/linux-azure-fde-5.15/5.15.0-1047.54~20.04.1.1
   https://launchpad.net/ubuntu/+source/linux-gcp-5.15/5.15.0-1042.50~20.04.1
   https://launchpad.net/ubuntu/+source/linux-gkeop-5.15/5.15.0-1028.33~20.04.1
   https://launchpad.net/ubuntu/+source/linux-hwe-5.15/5.15.0-84.93~20.04.1
   https://launchpad.net/ubuntu/+source/linux-ibm-5.15/5.15.0-1038.41~20.04.1
 
https://launchpad.net/ubuntu/+source/linux-lowlatency-hwe-5.15/5.15.0-84.93~20.04.1