WordPress has bugs and security holes just like any other content management system. When developers find those issues, they release updates to the WordPress core, themes and plugins. And it is your responsibility to apply those updates regularly to keep your website/blog secure and up to date.
This tutorial explains how to allow remote connections to the MySQL/MariaDB server on Ubuntu 18.04. The default behaviour of the Ubuntu MySQL Server blocks all remote connections. Which prevent us from accessing the database server from the outside.
This tutorial explains how to reset MariaDB root password in Ubuntu server 18.04 bionic beaver.
MariaDB server on Ubuntu does not need a password for connecting as a root user because the server-side plugin named unix_socket is used to authenticate clients which are connected from the local host using the Unix socket file.
MySQL server on Ubuntu 18.04 use Unix Socket plugin to authenticate MySQL root user by default. Unix socket also known as auth_socket authentication plugin authenticates the user using the OS credential. Which means a user can only log in If the operating system user name matches the MySQL user name specified by the client.
By default, FTP Connections are in Active mode. However, there is another mode called Passive FTP.
From the server, we need to enable passive FTP If the FTP client uses the passive mode to initiate the FTP connection .