WIRED: U.S. tried to sabotage N. Korea nuke program with Israeli Stuxnet worm, but failed

From WIRED:

     The targeted machines in Iran, like those in North Korea, are not connected to the internet. So the attackers had to devise ways to get the weapon onto those air-gapped machines. They did so by infecting five Iranian companies that are in the business of installing Siemens and other brands of industrial control systems at Natanz and other facilities throughout Iran. The attackers targeted these companies with the hope that contractors working at Natanz would carry the weapon into the well-guarded facility.
     While the plan worked beautifully in Iran, it ultimately hit a snafu against North Korea where the nuclear program is even more tightly controlled than Iran’s and where few computers—belonging to contractors or anyone else—are online and accessible via the internet.