pdlist. A passive subdomain finder

Author: gnc

Copyright: © 2019, gnc.

Date: 2019-07-25

Version: 0.1.0

PURPOSE

pdlist is a passive subdomain finder written in python3. This tool can be used
effectively to collect information about a domain without ever sending a
single packet to any of its hosts.
Given a domain like “example.com” it will find all the hosts which
have a hostname <something>.example.com or URLs strictly related to example.com.

In order to collect informations about subdomains the software queries different
publicly available websites, which at the moment are:

• threatcrowd
• urlscan
• hackertarget
• dnsdumpster
• crt.sh
• certspotter

pdlist is very user-friendly and lightweight since the only dependencies are
the following python modules:

• requests
• BeautifulSoup4

INSTALLATION

We can install pdlist simply by doing:

git clone https://github.com/gnebbia/pdlist
cd pdlist
pip install -r requirements.txt
python setup.py install

Notice that both pip and python should refer to version 3, so if you are not
using pyenv as I am doing you should probably substitute pip with pip3 and
python with python3.

USAGE

To have a list of subdomains passively of for example
example.com we can do:

pdlist example.com

we can also specify multiple domains, e.g.,;

pdlist example1.com example2.com

We can save the output in a text file by doing:

pdlist example.com -o example-list.txt

Notice that by default pdlist will also output hostnames which may not really
be proper subdomains of the specified domains, and this happens because those
subdomains are still related to the specified domains.

If we want to only output proper subdomains we can enable the strict mode by
doing:

pdlist example.com --strict

A usage example in the gif below:

NOTES

This is a minimalist passive domain finder, the aim of this project is to have
few dependencies, small code footprint and easily extensible.

If you want to extend the code it is enough to add a module in the source
package with a def parse(domains) method.

TODO

• Add more passive recon sources
• Modify the code to work in asynchrounous mode
• Generate fancy html reports

COPYRIGHT

Copyright © 2019, gnc.
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

1. Redistributions of source code must retain the above copyright
   notice, this list of conditions, and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions, and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

3. Neither the name of the author of this software nor the names of
   contributors to this software may be used to endorse or promote
   products derived from this software without specific prior written
   consent.

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