Hardening Login screen in Centos7

We can disable the user list shown on  the login screen in Centos 7. From security point of view it will be helpful to not list all users in the login screen.

In Centos 7  there are several schemas are define for gnome. You can list the available schemas using gsettings list-schemas command.

To disable user list on the screen we have to add entry in org.gnome.login-screen schema.

When we start Centos 7 in graphical target mode. We see login screen with user list as bellow:

                                        

Create file under /etc/dconf/db/gdm.d/ as follow:

1).  # vi /etc/dconf/db/gdm.d/00-login-screen

      [org/gnome/login-screen]

      disable-user-list=true

2) Update dconf database

  dconf is the command line utility used for writing and reading individual values or entire directories from dconf database.

  dconf-editor is the graphical utility for editing or viewing dconf database values.

    # dconf update

After updating gdm database logout from the gnome you will see bellow screen without user list.