The host at this IP address is obviously operated by cybercriminals. It is running a malware botnet controller which is being used to control infected computers (bots) around the globe using a trojan horse.
Malware botnet controller located at 40.90.210.21 on port 3054 TCP:
$ telnet 40.90.210.21 3054
Trying 40.90.210.21…
Connected to 40.90.210.21.
Escape character is ‘^]’
Referencing malware samples (MD5 hash):
a521f746f0ab71b078bf803283ca6858 — AV detection: 43 / 69 (62.32%)