I recently installed Ubuntu 26 on a Hyper-V VM for the first time—previously, installation of Ubuntu 24 went smoothly. However, when I boot up the new VM, it prompts that a "BIOS update" is required. This seems strange since it's a virtual BIOS. Has anyone encountered this issue and can explain its cause?
5 Answers
Did you accidentally disable Secure Boot? Sometimes toggling that can lead to strange messages during boot.
Make sure your host OS is updated and double-check the secure boot settings for your VM. Are you using Gen 2 VMs? That can affect how UEFI works.
Yes, the host OS is fresh, we’re using UEFI secure boot, and it is indeed a Gen 2 VM.
It might not actually need a BIOS update but rather an update to secure boot certificates. Sometimes, Ubuntu throws a misleading error message. What are your secure boot settings? Have you encountered any issues with the recent secure boot updates from Microsoft?
Great point! That could definitely be the reason. We have UEFI secure boot set up correctly, so it seems likely that's the issue.
Just a quick check—what generation is your VM? Just confirming it's Generation 2, right?
Yep, it’s Generation 2.
It sounds like a potential secure boot revocation list update that needs addressing. The VM can't update its "firmware" because that’s handled by the host, but if Ubuntu feels something is missing, it might throw that message. Try checking the CLI for more details.
Thanks! I’ll definitely look into that.
No, we intentionally keep it on. We use signed certificates and enroll everything properly, but it might be prompting for cert updates now.