In a blog post today, Marcus Sachs, director of the SANS Internet Storm Center, listed about 50 sites that contain the malicious pointers.
He urged system administrators to block network traffic to the sites until it can be confirmed they are free of malware. Users can be infected simply by visiting the websites.
Mikko Hypponen, chief research officer at F-Secure, said some of the hacked sites relate to the Super Bowl.
Sachs, meanwhile, reported that a number of attacks are targeting hospital or medical care sites.
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