....Fortunately, the malware was detected by F-Secure and likely competing antivirus packages as well. Additionally, a large percentage of connections to the attacker servers failed. On top of that, NanoCore runs only on Windows, so people visiting on machines running other operating systems were immune to the attack. PageFair's Blanchfield estimated that only 2.3 percent of people visiting one of the 501 affected sites during the attack would have been at risk of being infected. Still, the incident is the latest to show how people visiting known sites can still be exposed to drive-by attacks with serious consequences.