Courtesy of our friends at MOREnet
There is a report today of FakeAV malvertisements (malware distributed via advertising sites) within the Hotmail and Live.com advertiser suite. We know several MOREnet members host their e-mail on Live.com and many people use Hotmail on a regular basis. Remind your users that you have real Anti-Virus installed on your organization-owned computers. If you provide wireless access to users for connecting their own systems, remind them not to click on Fake Anti-Virus ads that may popup from visiting these sites.
stopmalvertising.com/malvertisements/alert-several-websites-hit-by-malvertisements has more information at the bottom of the page.