Vunerabilities

• If you use of old versions of Word Press, you WILL get hacked. Use the latest stable version. Recent Word Press Versions have plugged security vunerablities of the older versions
• Word Press, because of its widespread use, is one of the internet's most popular target for Spammers and Hackers. They are contantly seek exploits to get into your Word Press site.
• Basic WP installation does not hide the Admin login page. This enables brute force attacks on the password.
• There are plenty of reputable plugins available. Use WordPress recommended/reputable plugins. Do not use obscure plugins as they could contain malicious code.

WordPress Hardening Plugins

• Sucuri Security
• Wordfence
• All in One WP Security
• iThemes Security
• Shield Security

You can search for these plugins and install them via the WordPress Management Console.