In 2013, Kaspersky reported on a threat actor group they named “IceFog” that had been attacking a large number of entities related to military, mass media, and technology in South Korea and Japan. This group developed their own backdoor for both Windows and OS X. And just this year, Kaspersky published a report on a group they named "Careto/Mask" that utilized an open source netcat-like project designed to run on *nix and Windows systems named ‘sbd’ which they wrapped in a custom built installer for OS X.