TeslaCrypt appears to be a derivative of the original Cryptolocker ransomware. Ransomware is becoming an extremely lucrative business, leading to many variants and campaigns targeting even localized regions in their own specific languages. TeslaCrypt is interesting because it also targets and encrypts computer games files, such as saved games and Steam activation keys. The malware is usually distributed as an email attachment or through websites that redirect the victim to the Angler Exploit Kit. It is possible that these multiple variants are sponsored by the same threat actor.”]
Source: https://blog.talosintelligence.com/2015/04/threat-spotlight-teslacrypt-decrypt-it.html