I think I know what's up... If it's not a co-opt ad, then there's a chance its the TAPATALK Injector exploit. This explains why both CMS and ENWorld is giving off the warnings.
I've flagged this for [MENTION=1]Morrus[/MENTION] and [MENTION=52905]darjr[/MENTION], our excellent technical admin. They'll sort it out. In the mean time, it appears that the warning is in error, but I'm sure it's technically possible; make sure your malware software is up to date (good advice anyways). I'll be swapping to Explorer until we sort this out.