From 2-spyware.com
Wiot ransomware is a virus capable of affecting a large number of files just to later make a blackmail message addressed to the victim. The encryption[1] can start immediately after the infiltration, so the person whose files get altered cannot notice anything but the encoded files and a message demanding the payment. The file-locking process is pretty quick, so if you got the ransom note _readme.txt placed on the desktop and in other folders, your files are already corrupted. This is the threat from the Djvu ransomware family that is known for being very active for years and offering no decryption options for victims.