According to Maccentral, Intego is warning about another “trojan” virus for OS X. I use that in quotes because although it may match the technical definition, it’s hardly a threat, nor is it the result of some kind of security hole.
As others have said this is a “social engineering exploit”, preying on the stupidity of computer users. This Applescript is simply disguised with a custom icon, causing users to trust that it’s a Microsoft Office 2004 installer.
The reporting user explained that he downloaded the file through Limewire, thinking that it was a “beta” of Office. Yeah, and maybe burying Skittles will really yield a rainbow. Those who download this “trojan” and run it get what they deserve.