This is not something that can be tackled with AdBlock. It is a malware that links itself with certain text to create a green hyperlink, hovering on which you get that ad. I'd got this once too, don't know how as I'm usually very careful. The culprit was an addon called "websavee." Googling about it made me realize that there are tons of varieties of such malwares, each going by different names and ad networks, but all employing the same method. I suspect it also disables or uninstalls AdBlock; not sure about that though. On top of that, the addon also installs in your OS as a software and forces itself on startup and installs the addon every time you boot.
Here is a discussion about it on Google groups: https://productforums.google.com/forum/#!topic/chrome/RBVdrctIuIU
Here is a discussion about it on Google groups: https://productforums.google.com/forum/#!topic/chrome/RBVdrctIuIU