Bart Ransomware is being distributed by the same actors behind Locky and Dridex. This ransomware does not communicate with a Command & Control server, so it can encrypt a file even if its not connected to a computer. Bart will display a ransom note and demand 3 bitcoins in order to get the password for the victim’s zipped files. Unfortunately, at this time there is no way to decrypt these files for free. It is currently being distributed through SPAM emails that contain the subject Photos or Photo and contain ZIP attachments.
Source: https://www.bleepingcomputer.com/news/security/bart-ransomware-being-spammed-by-the-same-devs-behind-locky/