Sunday March 22, 2009, 7:44 pm
Conficker is a program that is spread by exploiting several weaknesses in Microsoft’s Windows operating system. Various versions of the software have spread widely around the globe since October, mostly outside the United States because there are more computers overseas running unpatched, pirated Windows. (The program does not infect Macintosh or Linux-based computers.)

An estimated 12 million or more machines have been infected. However, many have also been disinfected, so a precise census is difficult to obtain.