Java script tab pop-up

Everytime I click on anything in my Yahoo email, it opens another internet tab with this displayed:

javascript:'<script type="text/javascript">document.domain = "s.yimg.com";var rfiAdContent = window.parent["rfiAdContentad35f8b09f33d1c92375498ba76e1d73"];window.parent["rfiAdContentad35f8b09f33d1c92375498ba76e1d73"] = null;document.write(rfiAdContent);document.close();</script>'

Just annoying and not sure how to get rid of this...Thanks!