Here is how to do that (Note: be sure you are running the latest kernel before you start, and thanks to this post):
# cd /etc/yum.repos.d/VirtualBox will now appear in the Applications -> System Tools menu.
# wget http://download.virtualbox.org/virtualbox/rpm/rhel/virtualbox.repo
# yum install epel-release
# yum install dkms
# yum install VirtualBox-5.0
Before individual users can create VMs, they have to be added to the vboxusers group with:
# usermod -a -G vboxusers [user name]
Users added to the group can now start VirtualBox and install VMs.