WordPress 4.2.1 was released on April 27, 2015.
This is a Critical Security Release.
Because of the nature of this release, this update may be rolled out faster than normal, and checks against plugins and themes may be ignored if they take too long to confirm compatibility. Also, I wouldn’t be surprised if GoDaddy pushes this update automatically in order to protect their services as a whole. More information on this release can be found here:
I will be contacting each of you individually to schedule update times that work best for your needs as soon as possible.