[Calisto](https://attack.mitre.org/software/S0274) is a macOS Trojan that opens a backdoor on the compromised machine. [Calisto](https://attack.mitre.org/software/S0274) is believed to have first been developed in 2016. (Citation: Securelist Calisto July 2018) (Citation: Symantec Calisto July 2018)