Encrypting ransomware reappeared in 2013 with a worm known as "CryptoLocker". Distributed as either an attachment to a malicious e-mail or as a drive-by download, CryptoLocker encrypts data with the RSA-2048 algorithm on any local or network storage devices that the computer can access. While the public key is stored on the computer, the private key is stored on a command and control server; CryptoLocker demands a payment of US$300 with either pre-paid cash or Bitcoin to recover the key and begin unencrypting files, and threatens to delete the private key if a payment is not received within a certain timeframe.
so i can just do a hard reset and it'll be fine?
A hard reset doesn't decrypt your files. A couple of centuries worth of computation could, though.
Hey, at least they decrypt your stuff if you pay up..
Yeah, that's surprising.
The actual concept is pretty smart, too. The price is only $300 (effectively the price of a new computer). The only people dumb enough to actually download the virus are guaranteed to be dumb enough to not have backed up their files anywhere and are also much more likely to actually pay the sum of money.
Helpful advice from your friendly neighborhood Malwarebytes