Canonical released the first kernel security update for its latest Ubuntu 20.04 LTS (Focal Fossa) operating system series to address a single security vulnerability.
The security issue (CVE-2020-11884) patched in Ubuntu 20.04 LTS (Focal Fossa) was discovered by security researcher Al Viro in the Linux kernel for s390x systems. Apparently, the Linux kernel failed to perform page table upgrades for kernel sections that use a secondary address mode.
This could allow a local attacker to either crash the vulnerable, unpatched system by causing a denial of service or execute arbitrary code. In other words, systems running on the IBM Z (s390x) architecture could be made to crash or run programs as root (system administrator) under certain conditions.
The flaw can be patched by upgrading the kernel packages to linux-image 18.104.22.168.33, which is available for 64-bit, ARM64, and PPC64el systems too in OEM, lowlatency, lpae, and virtual flavors. A system reboot is required for the security issue to be addressed.
To update your installations, you can follow the instructions provided by Canonical at https://wiki.ubuntu.com/Security/Upgrades or run the
sudo apt update && sudo apt full-upgrade command in the Terminal app or the virtual console.
After installing the new kernel version, you may have to recompile and reinstall any third-party kernel modules you might have installed on your system, unless you manually uninstalled the linux-generic, linux-virtual or linux-powerpc standard kernel metapackages.
This Ubuntu 20.04 kernel security vulnerability was also patched in the latest Ubuntu Linux kernel security updates released for Ubuntu 19.10 and Ubuntu 18.04.4 LTS systems running Linux kernel 5.3, as well as Ubuntu 18.04 LTS and Ubuntu 16.04 LTS systems running Linux kernel 4.15.
Last updated 1 year ago