It all starts with an email.
"It's because they opened a link in an email attachment," said Kevin Gardner, Senior Computer Technician at Computer Rennaisance. "So they click on the link and follow through, and then their computer is struck by CryptoLocker."
The malware uses top-notch encryption to hold your computer files hostage.
"There's been viruses similar to this in the past. But this is the first one that has properly used encryption, so there's really no way to get the files back," said Shannon McMurtrey, Director of Cyber Security program at Missouri State University. "Once a person has this virus, their only option is to restore from backup."
The way the virus works is that when your computer is infected, your data will become encrypted, and you'll be alerted to pay a ransom.
The amount is usually around $300 and you can pay with cash, MoneyPack, or even by Bitcoin.
"Bitcoin is a fairly anonymous way of exchanging money," said McMurtrey. "So it's a perfect median for the bad guys to use."
Experts advise against paying a ransom. Instead, they encourage prevention.
"The best defense that we've seen against this is a good backup," Gardner said.
"Best practices are to use good antivirus software," McMurtrey said. "Microsoft provides a package called Microsoft Security Essentials, which is actually a pretty good package-- as long as it's installed and kept current."
The surest way to prevent catching the virus is to refrain from clicking anonymous links.
"Don't click on links in email," said Gardner. "That is the best additional defense, even if it's from a source that you trust."
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