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Alerts This Week
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Ubuntu 16.04: USN-5926-1 Critical: Kernel Denial of Service Threats

ubuntu
Calendar Grey March 6, 2023
Scroller Ubuntu
Tackling vital kernel vulnerabilities within Ubuntu's ESM versions; prompt updates are recommended for safeguarding.
Several security issues were fixed in the Linux kernel.

Summary

Several security issues were fixed in the Linux kernel.

Software Description:

- linux: Linux kernel

- linux-kvm: Linux kernel for cloud environments

- linux-aws: Linux kernel for Amazon Web Services (AWS) systems

- linux-lts-xenial: Linux hardware enablement kernel from Xenial for Trusty

Details:

Kirill Tkhai discovered that the XFS file system implementation in the

Linux kernel did not calculate size correctly when pre-allocating space in

some situations. A local attacker could use this to expose sensitive

information. (CVE-2021-4155)

Lee Jones discovered that a use-after-free vulnerability existed in the

Bluetooth implementation in the Linux kernel. A local attacker could use

this to cause a denial of service (system crash) or possibly execute

arbitrary code. (CVE-2022-20566)

Duoming Zhou discovered that a race condition existed in the SLIP driver in

the Linux kernel, leading to a null pointer dereference vulnerability. An

attacker could use this to ca...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service critical Ubuntu kernel local access memory exposure

Update Instructions

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

Ubuntu 16.04 ESM:
   linux-image-4.4.0-1117-kvm      4.4.0-1117.127
   linux-image-4.4.0-237-generic   4.4.0-237.271+1
   linux-image-4.4.0-237-lowlatency  4.4.0-237.271+1
   linux-image-generic             4.4.0.237.243
   linux-image-generic-lts-xenial  4.4.0.237.243
   linux-image-kvm                 4.4.0.1117.114
   linux-image-lowlatency          4.4.0.237.243
   linux-image-lowlatency-lts-xenial  4.4.0.237.243
   linux-image-virtual             4.4.0.237.243
   linux-image-virtual-lts-xenial  4.4.0.237.243

Ubuntu 14.04 ESM:
   linux-image-4.4.0-1116-aws      4.4.0-1116.122
   linux-image-4.4.0-237-generic   4.4.0-237.271~14.04.1
   linux-image-4.4.0-237-lowlatency  4.4.0-237.271~14.04.1
   linux-image-aws                 4.4.0.1116.113
   linux-image-generic-lts-xenial  4.4.0.237.206
   linux-image-lowlatency-lts-xenial  4.4.0.237.206
   linux-image-virtual-lts-xenial  4.4.0.237.206

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-5926-1

CVE-2021-4155, CVE-2022-20566, CVE-2022-41858, CVE-2022-42895,

CVE-2023-0045, CVE-2023-23559

Severity
critical
Lowest
Low
Medium
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Critical

March 06, 2023

Topics%20covered

Topics Covered

security advisory denial of service critical Ubuntu kernel local access memory exposure

Package Information

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