The popular content management and blogging software used by a huge percentage of the world’s blog sites had a security hole that could be exploited to take control of the web server, and attack code had been released in the wild. WordPress responded quickly, releasing a security update to patch the problem – but it only helps if admins ensure that it gets applied to their servers.
Read more here:
http://arstechnica.com/security/2015/04/27/just-released-wordpress-0day-makes-it-easy-to-hijack-millions-of-websites/
