This was on HN a few days ago: http://www.welivesecurity.com/2016/12/06/readers-popular-websites-targeted-stealthy-stegano-exploit-kit-hiding-pixels-malicious-a

This was on HN a few days ago: http://www.welivesecurity.com/2016/12/06/readers-popular-websites-targeted-stealthy-stegano-exploit-kit-hiding-pixels-malicious-ads/ http://www.welivesecurity.com/2016/12/06/readers-popular-web... Basically ads that exploit you without you clicking on them. I don't know if it was on the acceptable ads list and you had a old copy of adobe acrobat, then you would be hacked. They didn't mention what sites but users in Central Europe got it on popular websites. Sites you'd probably trust. Other than static ads between the hosting site and the site that wants to advertise without a middleman ad network, I don't trust any ads. In the case listed previously, a human is more likely to review the ad, making it safer. Since I care about not getting hacked, the obvious conclusion for me is to block all ads.