installing VirtualBox

For Kubuntu 18.04, add deb https://download.virtualbox.org/virtualbox/debian bionic contrib to /etc/apt/sources.list, then use wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add - && sudo apt-get update && sudo apt-get install virtualbox-5.2.

To enable USB 2.0 and 3.0, download the proprietary VirtualBox Extension Pack (matching up its version number with the VirtualBox version already installed, found with Help > About VirtualBox...) and install it with File > Preferences > Extensions. Use sudo usermod -aG vboxusers foobar to include the host user in the vboxusers group, where foobar is the username. Reboot. Use Settings > USB > USB 2.0 (EHCI) Controller to set USB 2.0 instead of 1.0.

Attention

Running a virtual machine may require enabling hardware virtualization in BIOS.

Personal experience

• Works in Kubuntu 18.04 on Slim.

licensing

No rights reserved: CC0 1.0.

prior work

• The installation instructions and the bulk of the installation script were introduced to me by a page on the VirtualBox website.
• The method of installing the VirtualBox Extension Pack was introduced to me by an answer on Ask Ubuntu by Takkat.
• The possibility of enabling hardware virtualization in BIOS was introduced to me by an answer on Super User by duDE.