InformationWeek > Security > Virus Posing As Microsoft E-Mail Spreads Fast > September 19, 2003: "
Less than 24 hours after first being detected, the Swen blended-threat worm picked up steam Friday, gained a foothold in the United States and the United Kingdom, and accounted for more than 35,000 interceptions by E-mail filtering firm MessageLabs.
Swen, also called W32/Swen@MM, Gibe, and W32/Gibe-F, masquerades as E-mail from Microsoft and purports to carry a security update as its file attachment. "

Here we go again!