Perhaps the most famous example of malware disseminated by USB is the Stuxnet worm, which was first discovered in 2010. This malware targeted four zero-day exploits in Windows 2000 through to Windows 7 (and Server 2008) and wreaked havoc on around 20% of Iran’s nuclear centrifuges. Since these facilities were not accessible via the internet, Stuxnet is believed to have been introduced directly using a USB device.