Microsoft has issued security advisory (929433) (here)stating that there is an active “zero-day” exploit (here) taking advantage of a vulnerability in Microsoft Word , a vulenrability originally made public on May 12th, 2006. So technically it is really a 207-day, but that is neither (here) nor (there)
“Microsoft is investigating a new report of limited “zero-day” attacks using a vulnerability in Microsoft Word 2000, Microsoft Word 2002, Microsoft Office Word 2003, Microsoft Word Viewer 2003, Microsoft Word 2004 for Mac, and Microsoft Word 2004 v. X for Mac, as well as Microsoft Works 2004, 2005, and 2006.”
There is no available patch, no AV signatures you can download at this point, and the work-around from MS is to not open word documents. They also suggest you implement a personal firewall, update AV and keep MS products up to date, again all of which do nothing to stop this atack, but have become the equivalent of “if you sit too close to the TV you will go blind” advise.