GRUB2 Boot Failure Issues Fixed in Debian and Ubuntu, Update Now

Last week, I was reporting on the BootHole vulnerability (and some other seven flaws) found in the GRUB2 bootloader, which is used by almost all GNU/Linux distributions out there. The issues opened up systems using Secure Boot to attacks, allowing local attackers to bypass UEFI Secure Boot restrictions and execute arbitrary code. Due to a highly coordinated effort between the security researchers who discovered the vulnerability and Linux OS maintainers, most GNU/Linux distributions were able to provide patches for their users. However, for some, these patches broke the Secure Boot implementation and left people with unbootable systems.