Errorsafe advertisement

Normally I don't mind the ads, but recently I've gotten a really aggressive Errorsafe ad when I visit Coasterbuzz. It comes with question boxes, opens itself again and doesn't allow closing it down. It claims to begin some sort of security test on the users computer. Really fishy.

It could be that I've picked up some malicious adware, but the ad has started on two different computers right when I visit Coasterbuzz. Is it a valid part of the site advertisement? Main reason I don't mind Coasterbuzz's ads is a) they go for a good cause and I don't want to spend the money for membership b) they are generally pretty harmless and easy to ignore.

I doubt it's from this site. I could be wrong, but my ad firms don't allow that kind of thing.