Automated exploit kits are typically rented and maintained by their owner. The subscription model provides the user software updates to ensure a consistent number of new exploits and features for setting up and delivering broad-based attacks. The most popular toolkit had been the Black Hole Exploit Kit, which has fueled a variety of attacks and could be purportedly leased for about $700 for a three-month subscription. Following the arrest of kit's owner by Russian authorities, other attack toolkits have taken its place, and security researchers say there are dozens of them available that vary in sophistication. Dell said the leasing fees for the Sweet Orange Exploit Kit was set at $450 a week or $1,800 a month.