The Maktub Locker comes in a spam campaign pretending to be a Terms-Of-Service update update. The name originates from the Arabic word maktub which means this is written or this is fate The price of the ransom note starts with 1.4 BTC and increases with time. The ransom note is only available in English, and the website is available only in English. It comes with a demo, allowing the decryption of 2 selected files. The code is written in a well-written crypter/FUDpter, so the code is not readable at first.”]
Source: https://blog.malwarebytes.com/threat-analysis/2016/03/maktub-locker-beautiful-and-dangerous/