The host at this IP address is running a malware botnet controller which is being used to control infected computers (bots) around the globe using a trojan horse.
AZORult botnet controller located at 104.21.33.51 on port 80 (using HTTP POST):
hXXp://nnpcoil.buzz/kendrick/index.php
$ dig +short nnpcoil.buzz
104.21.33.51
Referencing malware binaries (MD5 hash):
aa3c88aa7193bc0bb4ecf9638e65d4be — AV detection: 27 / 70 (38.57)
Other malicious domain names hosted on this IP address:
jzl.hostgatoramisulpride.site 104.21.33.51
www.ugpower.top 104.21.33.51
nnpcoil.buzz 104.21.33.51