Cryptolocker is a malware threat that gained notoriety over the last years. It is a Trojan horse that infects your computer and then searches for files to encrypt. This includes anything on your hard drives and all connected media — for example, USB memory sticks or any shared network drives.
In addition, the malware seeks out files and folders you store in the cloud. Only computers running a version of Windows are susceptible to Cryptolocker; the Trojan does not target Macs. Once your desktop or laptop is infected, files are "locked" using what's known as asymmetric encryption.
This method relies on two "keys," one public and one private. Hackers encrypt your data using the public key, but it can only be decrypted using the unique private key they hold. The Cryptolocker virus will display warning screens indicating that your data will be destroyed if you do not pay a ransom to obtain the private key.
