Stuxnet: It's the real thing, baby

At least four zero-day vulnerabilities were used. Remember, these were classified as "zero-days" once we found out about them back in June/July -- which means the folks that discovered the vulnerabilities could have been using them/testing them for 12-24 months(?) before we even knew they existed.

via Stuxnet: It's the real thing, baby | The Best Defense.