VeraCrypt was apparently installed during the upgrade to 18.04, but won't open documents. VeraCrypt icon showed up. I tried uninstalling, then reinstalling VeraCrypt, and now the icon is gone, and typing 'veracrypt' (or 'sudo veracrypt') in the command-line now returns "command not found"
sudo ./veracrypt-1.22-setup-gui-x64
for the graphical GUI setup. Worked for me.