1. Ubuntu Security Notices
  2. USN-6383-1

USN-6383-1: Linux kernel vulnerabilities

Publication date

19 September 2023

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

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...

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

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
23.04 lunar 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
22.04 jammy 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

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References

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