First of all, check that hardware virtualization is enabled in your UEFI setup.
You need to have packages virtualbox-dkms and linux-headers installed (together with all their dependencies, but you don’t have to check them manually). linux-headers must be of the same version as linux-image. That’s all that you need to get driver properly built. Don’t listen those users who recommend you to remove and reinstall these packages or install additional packages manually, this kind of magic doesn’t work.
Also note that you cannot use kvm and virtualbox simultaneously. If you are using some kvm-based virtualization system, it causes a conflict.