virtualbox.org

Hello

I cant start a Ubuntu 20.04 host - 22.04 guest yesterday on Ubuntu 20.04 host .

It shows the below error for a second and then turns itself off.

RETBleed: WARNING: Spectre v2 mitigation leaves CPU vulnerable to RETBleed attacks, data leaks possible!

Thanks

i was doing some troubleshooting.

looks like when i have an usb 3.0 external drive attached to the VM it doesnt boot showing this error message "RETBleed: WARNING: Spectre v2 mitigation leaves CPU vulnerable to RETBleed attacks, data leaks possible!"

If i remove that USB 3.0 drive from options then VM boots up.

Why is this happening and how to resolve this issue?

thanks

Same issue as Issue connecting USB storage to Win10 guest.

As a workaround, try disconnecting any USB3 device before starting the VM, and re-adding them when the VM is running.

Hello fellow ubuntu users, i had the same problem as you do. I could not start my Ubuntu 20.04 vm, it could not read the disk or something.
The problem is simple to solve, although the warning still remains but whatever.

1. Go under Tools>Preferences>Extensions and uninstall Oracle VM VirtualBox Extension Pack.
2. Go to virtualbox official site and under wiki/Downloads (sorry, first post and cannot use urls, lol) and download the latest VirtualBox Extension Pack (shold be 6.1.36 as of today) and install it.

In my case this was the problem. I just updated vbox to a newer version (6.1.34 -> 6.1.36) and after that it did not booted the vm anymore. After updating the extension pack everything worked again, hope this helps.

Well thanks for trying to help, but the log above shows the 6.1.36 extension pack is already being used.

Mismatched extension pack is a common user error, we volunteers would have picked up on that quickly if that was the only issue in 6.1.36.

I restore my vm from a backup and it works. I think the problem is I didn't take the last ubuntu updates.