After reading this I decided to downgrade my Ubuntu machine for now until it's figured out. There are instructions here: https://wiki.ubuntu.com/SecurityTeam/Kn

After reading this I decided to downgrade my Ubuntu machine for now until it's figured out. There are instructions here: https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypass https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2Secu... under the heading "DOWNGRADE `GRUB2`/`GRUB2-SIGNED` TO THE PREVIOUS VERSION FOR RECOVERY" Under the heading is a small shell script that will download the old debs for you. Note that for it to work and not have wget spam 404:s, you have to update the entire GRUB2_LP_URL and GRUB2_SIGNED_LP_URL to the links in the little table. At first glance it looks like you only have to change GRUB2_VERSION and GRUB2_SIGNED_VERSION.