How was it installed?
The official apt repositories are known to have old (read thoroughly tested and stable) versions for some software packages. In that light, VirtualBox was installed through the latest stable .deb installer downloaded from the official website, with the version number at the time being 6.1.28-147628. When the new stable version 6.1.30-148432 became available, following are the steps that were followed to set it up.
The Process
First, we need to obtain a copy of the .deb installer for the new package. Then we need to identify the package name of the currently installed version of the software package as follows (i.e. virtualbox).
sudo dpkg -l | grep -i virtualbox
Then we can remove the package using the package name found out from the output of above command (i.e. virtualbox-6.1).
sudo dpkg -r virtualbox-6.1
Now we are ready to install the newer package on the system as follows (i.e. virtualbox-6.1_6.1.30-148432~Ubuntu~eoan_amd64.deb).
sudo dpkg -i virtualbox-6.1_6.1.30-148432~Ubuntu~eoan_amd64.deb
Once this is done, the newer version shall be available on the system, if any dependencies are not satisfied, the names will be listed and we’ll need to install them as well. Finally, the name of the installed package shall be found out by listing the packages and grepping those as was done previously.