So how can individuals and SMBs protect themselves from ransomware? "The No. 1 thing is to make backups" of critical files, said Nate Villeneuve, a principle threat intelligence analyst at FireEye, a cybersecurity firm in Milpitas, California. Beware, however, that any servers, hard drives or other backup sources connected to a network will probably be infected, too. It may be wise, therefore, to back up onto a separate source or a cloud storage service.
"Also, keep operating systems, browsers and plug-ins, especially Flash and Java, up to date," Villeneuve said. In other words, when you see those update notices pop up on your screen, do as they say. Off-the-shelf antivirus software adds another layer of protection, and FireEye, Symantec, Trend Micro, Dell and other cybersecurity vendors offer solutions for SMBs.
Experts urge everyone to be extra vigilant for spam, even if it looks legitimate, and to never download an unknown file. Many companies run drills, sending employees fake emails to see how many get fooled. "Use it as a teaching moment, not ashaming moment," Haley said.
Meanwhile, the FBI, other law enforcement agencies and cybersecurity vendors are collaborating in the hunt for ever-evolving ransomware and "the bad guys" who scramble to stay one step ahead of the cyber cops. It's a perpetual cat-and-mouse game, but Ayrapetov, for one, is optimistic that ransomware's days are numbered, with a caveat: "In about two years, it will probably be difficult enough for the malware writers that they'll start looking for something new."
— By Bob Woods, special to CNBC.com