Knockpy is a python tool designed to enumerate subdomains on 

a target domain through a wordlist.

It is designed to scan for DNS zone transfer and to 

try to bypass the wildcard DNS record automatically

if it is enabled. Now knockpy supports queries to VirusTotal subdomains,

Installation :

$ apt update && apt upgrade

$ apt install git 

$ apt install python2

$ apt install python
$ pip2 install dnspython


$ git clone https://github.com/guelfoweb/knock.git

$ cd knock $ python2 setup.py install

usage :

$ knockpy -h

it shows how you can use this tool

$ knockpy domain.com