Comment 9 for bug 1899233

I'm also seeing the same issue on Ubuntu 20.04 LTS after updates pulled in a 5.8 kernel as part of HWE. Kernel module build errors were returned during the update and indeed VirtualBox VMs fail to start when running the 5.8 kernel. If I instead boot from a 5.4 kernel (selected from the GRUB menu) I can still start VirtualBox VMs.

Switching to VirtualBox's upstream repo/packages is not preferred option for me. The last I checked, admittedly a few months ago, their upstream packages still depend on Python 2 whereas the VirtualBox packages in Ubuntu's repos depend on Python 3. Plus I've historically found VirtualBox's upstream repo servers intermittently unreliable, the typical cause of errors when updating my APT cache (e.g. "apt(-get) update").