ImageSource CTB LOCKER (Curve-Tor-Bitcoin Locker) also known by Critroni is an example of file encrypting malware infections. The ransomware was released middle of July 2014 targeting windows OS. Curve - comes from its persistent cryptography based on elliptic curves, which encrypts the affected files with a unique RSA key. Tor - comes from the malicious server placed in onion-domain which is very difficult to take down. BitCoin- refers to the possibility to pay in BitCoins, avoiding normal payment systems that can lead back to attackers. **CTB-Locker is a ransomware variant that first encrypts the files, then claims you have 4 days (96 hours) to make the payment, and if the victim doesn't send money in time, their files gets permanently encrypted.