Cybercriminals have already figured out how to infect computers, and scareware makers have figured out how to frighten people into taking regrettable actions online (such as downloading malicious software). It’s not surprising that a new trend combines infection with threats in a phenomenon called “ransomware.” An infected machine appears to be disabled until the user pays money to the criminal who is, essentially, holding their computer “hostage.”
Sometimes the computer has really been encrypted by an outside party, and the user has to contact that outside party in order to get that key—usually for a hefty price. Other times, the ransomware threat is empty, but it’s still convincing enough that people fork over the cash. (In one particularly devious twist, one ransomware threat displays on the user’s screen with a pornographic image in the background, dramatically minimizing the chances that the user will seek technical help.)

While these threats could propagate through any number of sites—including many legitimate ones—it’s more likely that they’ll appear on sites that promote free downloads, such as freeware and pornography sites. So if you want to steer clear of ransomware, start by making sure you’re sticking to the Internet equivalent of well-lit streets. Use a good antivirus program that can spot malicious threats before they’re downloaded to your computer. And if you still end up on the wrong end of a ransomware threat, get technical help immediately—there’s a chance that the situation can be remedied without making cyberthieves richer.

-Exerp from web