=========================================================================Ubuntu Security Notice USN-5600-1
September 05, 2022

linux-hwe-5.4 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description:
- linux-hwe-5.4: Linux hardware enablement (HWE) kernel

Details:

Asaf Modelevsky discovered that the Intel(R) 10GbE PCI Express (ixgbe)
Ethernet driver for the Linux kernel performed insufficient control flow
management. A local attacker could possibly use this to cause a denial 
of service. (CVE-2021-33061)

It was discovered that the virtual terminal driver in the Linux kernel 
did not properly handle VGA console font changes, leading to an 
out-of-bounds write. A local attacker could use this to cause a denial 
of service (system crash) or possibly execute arbitrary code. 
(CVE-2021-33656)

Update instructions:

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

Ubuntu 18.04 LTS:
   linux-image-5.4.0-125-generic   5.4.0-125.141~18.04.1
   linux-image-5.4.0-125-generic-lpae  5.4.0-125.141~18.04.1
   linux-image-5.4.0-125-lowlatency  5.4.0-125.141~18.04.1
   linux-image-generic-hwe-18.04   5.4.0.125.141~18.04.105
   linux-image-generic-lpae-hwe-18.04  5.4.0.125.141~18.04.105
   linux-image-lowlatency-hwe-18.04  5.4.0.125.141~18.04.105
   linux-image-oem                 5.4.0.125.141~18.04.105
   linux-image-oem-osp1            5.4.0.125.141~18.04.105
   linux-image-snapdragon-hwe-18.04  5.4.0.125.141~18.04.105
   linux-image-virtual-hwe-18.04   5.4.0.125.141~18.04.105

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-5600-1
   CVE-2021-33061, CVE-2021-33656

Package Information:
   https://launchpad.net/ubuntu/+source/linux-hwe-5.4/5.4.0-125.141~18.04.1