Sadly, sometimes, stuff happens.
It happened here.
The good news is no articles were affected. The review and pending post system caught it all. The bad news is the captcha and user/subscriber registration system is clearly not tight enoug, and a whole pile (and I mean a massive number) of spam accounts got registered.
Which means, in order to control the spam, I have had to delete all user accounts and remove the “submit an article” system for now.
If you would like to submit content, please see us over in Facebook.