dnsbf.py - Python script for Reverse dns search in a subnet (dns brute force)

The first step of a penetration test is to discover hosts in a subnet. In this aim, DNS is your second best friend (after Google :).First, to know which subnet (ex: 72.14.204.0/23) is associated to a hostname (ex: www.google.fr), you can use the Whois database (ex: with a site as http://www.robtex.com).
Then, to know which hosts are declared in DNS database in this subnet, you can use dnsbf.py :)
dnsbf.py is a script, written in Python, which conducts a Reverse DNS search for all the IPs in a subnet.

source code available: http://code.google.com/p/dnsbf/source/browse/trunk/dnsbf.py