I can confirm that this has been ongoing with a website that I operate. Basically, a malicious Adsense ad will redirect a page when it loads. I've blocked numerous malicious advertisers from the site, but a new ones have sprung up. It was so bad that at one point I had to disable all rich media ads.

Obviously, Google has not officially commented on this. I wonder how widespread it is?

I've noticed this on several sites I frequently visit (and have whitelisted in adblock). Try to do the right thing and support my favorite sites but of course a handful of bad actors make things miserable for everyone.

This is a much better link: http://blog.sucuri.net/2015/01/adsense-abused-with-malvertis...

But it is pretty amazing to read that thread. One should note that it has lots of participation over the last couple of weeks but clearly Google has a big issue here.

As a user I have experienced this same issue. Also from Google Adverts. Seems the bad guys have been making a lot of headway recently.