Why is this?

[wmxuan666]

┌──(root💀kali)-[/home/kali/exploit-CVE-2015-3306-master]
└─# ./exploit.py --host 127.0.0.1 --path "/var/www/html/" --port 21 1 ⨯
[+] CVE-2015-3306 exploit by t0kx
[+] Exploiting 127.0.0.1:21
Traceback (most recent call last):
File "./exploit.py", line 62, in
main(args)
File "./exploit.py", line 53, in main
exploit.run()
File "./exploit.py", line 45, in run
self.__connect()
File "./exploit.py", line 19, in __connect
self.__sock.connect((self.__host, self.__port))
File "/usr/lib/python2.7/socket.py", line 228, in meth
return getattr(self._sock,name)(*args)
socket.error: [Errno 111] Connection refused

[wmxuan666]

Please help me!