security pros disassembling and analyzing the Stuxnet code have discovered that it was designed to specifically target SCADA components made by companies in IRAN and Finland, and only those operating at high frequencies, that are mostly used in nuclear facilities. Once it discovered those, it was designed to change the operating frequencies of them, which affects the associated motors, at short intervals over months, thereby disrupting the systems over lengthy periods of time.
i.e. targeting non-regulated, non-uranium enrichment systems used for full nuclear production.
Register link: http://www.theregister.co.uk/2010/11/15/stuxnet_jigsaw_completed/
