I think having ....... Plus installed has protected me from running into the same problem. I believe there were at least two similar "virus" attacks in the last couple of months. May not be exactly the same as this one you guy are running into, but they are all ad-feeder-related (I think).

Malware ad on FT are very bad form

Virus on FT?

While I understand it's nearly impossible to have a virus-free virtual world nowadays, is there a way to prevent this sort of "attacks" more effectively from our House of Miles?