Not sure this is an appropriate forum for this, but maybe some fellow SPers have come across this and can point me in the right direction...

I have a Lenovo laptop running Windows 7, and have started experiencing pop-up windows with phishing attacks/attempts when I do an online purchase. The pop-up is one of those slightly different URL windows that looks very much like the site I'm actually browsing. Not unlike many phishing sites/pages. However in this case the page is customized to match the site I'm on, for example Wells Fargo. I also went to make a purchase on the Philadelphia Phillies website and the same thing happened. I got a phishing pop-up that looks like it's a legitimate part of the Phillies site.

McAfee software running on the computer is up-to-date and detects no viruses or spyware.

What else could this be? Anyone ever see such a sophisticated phishing mechanism before?