The Kronos malware is believed to have originated from the leaked source code of the Zeus malware, which was sold on the Russian underground in 2011. Kronos continued to evolve and a new variant of Kronos emerged in 2014 and was reportedly sold on the darknet for approximately $7,000. Kronos is typically used to download other malware and has historically been used by threat actors to deliver different types of malware to victims.
After remaining dormant for a few years, the Kronos banking trojan reemerged in 2018, under the name Osiris, and was used in a banking trojan campaign. While there were some differences between the two strains, both Osiris and Kronos shared the same technique for stealing information.