For general information, I'm
reasonably experienced with this stuff. I disinfect other people's machines daily. I'm also pretty confident about the security of my town's Internet service, because I built it.
I run Malwarebytes regularly. It finds nothing. I have cleaned out all the Launch*s, Startups, Plugins, site cookies, etc. It doesn't make a difference. None of that has helped this particular problem.
Other Apple users are
describing the same symptoms. Only Safari, only certain websites, tied to ad deliveries. But on some big name websites (that I rarely visit) like CNN and NYT.
Wordpress sites are implicated, visibly serving up the same ads as the Keystone Forum, CNN, etc.
I have the bogus site redirected to 0.0.0.0 in my hosts file to avoid the phishing page, but I still can't spend more than five seconds on a Keystone forum page that serves ads before I get hijacked to a "can't connect to URL" screen. (Conversely, I can spend forever on my profile screen because there are no ads there.)
Looks like I'm going to have to resort to Tapatalk and Firefox until the ad delivery aggregation company gets its act together.
UPDATE: I strongly suspect the reason that Firefox isn't being victimized by this is because it is apparently blocking all the ads!