Just threw together a very simplistic shell script that will:
1. Add the Virtualbox repository to /etc/apt/sources.list and will automatically build it by pulling the “Codename” variable from ‘lsb_release’.
2. Download and install the GPG key associated with the Virtualbox repository.
3. Perform an ‘apt-get update’ and install Virtualbox with no prompts.
You can checkout the code from the Github below and the script is ‘build_vbox’.