Is WinCC OA affected by the Virus Stuxnet?

Some malware, a so-called Trojan, is currently circulating which affects Microsoft Windows PCs with WinCC and PCS 7. WinCC Open Architecture installations are not affected, because of different software architecture (e.g. different dll ports) and different communication behavior compared to WinCC.

You will be receiving information here on the latest developments and the measures recommended by Siemens:
http://support.automation.siemens.com/WW/view/en/43876783