One-third of the top 10 botnets identified by Fortinet’s FortiGuard Labs are nearly 10 years old. ZeroAccess, Jeefo, Smoke, Mariposa, Grum/Tedroo, Lethic, Torpig, SpyEye, and Zeus are among the most prevalent botnet infections in February. Botnet business is as lucrative as ever, and plenty of botnet activity goes unseen. Professional botnet services charge thousands of dollars per month for bots and technical support.”]
Source: https://www.darkreading.com/attacks-breaches/botnet-business-booming