Ubuntu comes with default guest account. It does not require password to login. It is possible to turn it off by following procedure
Ubuntu comes with default guest account. It does not require password to login. It is possible to turn it off by following procedure:
Open /etc/lightdm/lightdm.conf:
sudo gedit /etc/lightdm/lightdm.conf
Add the following line
allow-guest=false
Restart the lightdm to apply:
sudo restart lightdm
And done