[Royal](https://attack.mitre.org/software/S1073) is ransomware that first appeared in early 2022; a version that also targets ESXi servers was later observed in February 2023. [Royal](https://attack.mitre.org/software/S1073) employs partial encryption and multiple threads to evade detection and speed encryption. [Royal](https://attack.mitre.org/software/S1073) has been used in attacks against multiple industries worldwide--including critical infrastructure. Security researchers have identified similarities in the encryption routines and TTPs used in [Royal](https://attack.mitre.org/software/S1073) and [Conti](https://attack.mitre.org/software/S0575) attacks and noted a possible connection between their operators.(Citation: Microsoft Royal ransomware November 2022)(Citation: Cybereason Royal December 2022)(Citation: Kroll Royal Deep Dive February 2023)(Citation: Trend Micro Royal Linux ESXi February 2023)(Citation: CISA Royal AA23-061A March 2023)