Ransomware made its debut in August 2018, but only three organizations were hit with Ryuk infections over the course of the first two months of its operations. Ryuk, unlike most ransomware, is only used for tailored attacks and its encryption scheme is purposefully built for small-scale operations. McAfee Labs suggests that Ryuk case is that of a cybercriminal operation developed from a toolkit offered by a Russian-speaking actor. Researchers dont currently know who is behind the outbreak.”]
Source: https://hackercombat.com/ryuk-ransomware-too-early-to-predict-the-actors/