Since 2011, security firm Blue Coat Systems has been tracking malnets: extensive distributed network infrastructures embedded in the Internet and designed to deliver mass-market attacks on a continuous basis. These malnet infrastructures are like the proverbial Lernaean Hydra--chop off one head, like a botnet it has produced, and two more spring up to take its place.

In just six months, the number of malnets tracked by Blue Coat Security Labs has rocketed up 300 percent from 500 to 1,500.