Comment 106 for bug 1736116

Locutus's xenial-proposed fix works great for me on the stock 4.13.0-37-generic kernel on my amd64 laptop.

Here's how I installed that fix on my 16.04 machine:

Start software-properties-gtk
        "Developer Options" tab
        Check "Pre-released updates (xenial-proposed)"

sudo apt update
sudo apt install virtualbox virtualbox-dkms virtualbox-ext-pack virtualbox-guest-utils-hwe virtualbox-guest-x11-hwe

Go back to software-properties-gtk and un-check pre-release to get off the bleeding edge (otherwise your next apt update will grab lots of proposed fixes).

Reboot to get the new dkms kernel packages, or manually install them like this:

sudo rmmod vboxpci vboxnetadp vboxnetflt vboxdrv
sudo depmod -a
sudo modprobe vboxdrv

Start virtualbox, and your VMs should work now even with the new kernel.