Installing “Guest Addition”, gives a better user experience with VirtualBox VMs (e.g. proper mouse and screen integration, as well as folder sharing). This is why since Kali Linux 2019.3, during the setup process it should detect if Kali Linux is inside a VM. If it is, then automatically install any additional tools (in VirtualBox’s case, virtualbox-guest-x11). The Guest Addition is also pre-installed in the Live image since Kali Linux 2021.3.

You must use VirtualBox 4.2.xx or higher in order to take advantage of the improvements, including compatibility updates, and enhanced stability of both the core application and the Guest Additions.

Should you decide to create your own VirtualBox installation of Kali Linux (rather than using our pre-made VirtualBox images), and you want to force a manual reinstall of virtualbox-guest-x11 (as something has gone wrong), first make sure you are fully updated, then enter the following:

kali@kali:~$ sudo apt update
[...]
kali@kali:~$
kali@kali:~$ sudo apt install -y --reinstall virtualbox-guest-x11
[...]
kali@kali:~$
kali@kali:~$ sudo reboot -f
kali@kali:~$

For older versions of Kali Linux, here is our previous guide.