WordPress is so ubiquitous these days on the web, but hopefully more developers will keep up with the security needs of their sites or at least delegate to someone to maintain after their site is built.
This ‘Wordfence’ security plugin is very impressive. It can do a site scan, block IPs or countries [China, anyone?], and give a live screen of current connections. It does much more as well, especially if the free version is upgraded to the paid version.
It has over 1 million installs as of September, 2015. There is a reason for that – even the free tools are very useful and can provide a fair amount of security. I recently installed this plugin on ‘Riguy’ and it is exactly what is needed for a security blanket.