From 2-spyware.com
Rrbb ransomware infects the machine quickly and can spread using malicious files, and other threats. The payload of the file virus can be distributed using spam emails or pirating software platforms, torrent sites, and p2p services. This particular family that the heat belongs to is known for spreading using Adobe licensed versions and game cracks for NBA and FIBA packages.
The threat infiltrates the machine quickly and silently, but the symptoms are not present for a while. Rrbb ransomware virus encodes files and marks them with .rrbb appendix that indicates the name of the infection. This appears at the end of the locked file when the ransom note _readme.txt also is placed on the desktop and in other folders.