Malicious URL Detected on All eBay Auction Pages.

This just started today on my Internet Explorer. Only on eBay auction pages I get the avast warning pop-up with this information on it;

Process; C:/Program Files.…\iexplore.exe

Infection; URL:Mal

Object; http:/…pixel?t=2id=2349022random=13
Any advice on how to clean my computer to get rid of this? Thanks!