If you are wondering what this has to do with the hacking, I would like to make you recall the incident that took place in June 2007. The SQL injection exploit of enabled hackers to gain access to entire databases worth of account user names and passwords. It was only when the WordPress team remedied the situation with a security patch that they came to know the main reason which was usage of outdated version and not updating the latest one which made the task of the hacker easier. Now you can well imagine how further delay in latest stable updates when available can help make hacking easy.
I have already talked about updating the WordPress to latest version. This one is like taking anther step. It is a wise idea to prevent potential hackers from knowing what version of WordPress you’re using. This will make it difficult for them to figure out which exploits will work to hack your website. remove_action(‘wp_head’, ‘wp_generator’); addition to the functions.php file will hide the WordPress version