Adobe is the Winner!

Microsoft Word has been dethroned as the most likely point-of-entry for rogue software.

Files based on Reader were exploited in almost 49 per cent of the targeted attacks of 2009, compared with about 39 per cent that took aim at Microsoft Word. By comparison, in 2008, Acrobat was targeted in almost 29 per cent of attacks and Word was exploited by almost 35 per cent.

So, either use an alternative such as Foxit Reader or for a quick 'n dirty fix: Open Adobe Reader, click onEdit, Preferences, JavaScript, and uncheck the enable JavaScript box.