DNSMAP Tutorial | DNS Network Mapper Information Gathering | KYB Tutorial 3

Hackingloops is back with another Know Your Backtrack Tutorial. In this tutorial, we will be learning DNSMAP Tool for DNS information gathering. DNSMAP, as the name suggests, is DNS Network Mapper, which is used for multiple purposes. Basically, DNSMAP is an passive Network Mapper, often called a sub domain brute force tool. This tool is mainly used by penetration testers and hackers for DNS and sub domain information gathering. It is similar to most other DNS information gathering tools except for a significant feature. 

DNSMAP Tutorial KYB 3 Hackingloops

 

Key Features of DNSMAP Tool on Backtrack:

• Obtain all A records (i.e. IP addresses) associated to each successfully brute forced sub domain, rather than just one IP address per sub domain.
• Abort the brute forcing process in case the target domain uses wildcards.
• Ability to run the tool without providing a word list by using a built-in list of keywords.
• Brute forcing by using a user-supplied word list (as opposed to the built-in word list).
• Saving the results in human-readable and CSV format for easy processing.
• Improved built-in subdomains wordlist.
• New bash script (dnsmap-bulk.sh) included which allows running Dnsmap against a list of domains from a user-supplied file. i.e.: brute forcing several domains in a bulk fashion.
• Bypassing of signature-based Dnsmap detection by generating a proper pseudo-random sub domain when checking for wildcards (Unique Feature).

 

Why to use DNSMAP Tool ?

 

1. Find interesting remote access servers.

2. Find badly configured and/or unpatched servers.

3. Find new domain names which will allow you to map non-obvious/hard-to-find net blocks.

4. Occasionally you find that some brute forced sub domains resolve to internal IP addresses (RFC 1918). This is great as sometimes they have very up-to-date “A” records, which means that it *is* possible to enumerate internal servers of a target organization from the internet by only using standard DNS resolving (as opposed to zone transfers for instance).

5. Discover embedded devices configured using Dynamic DNS services.

 

How to use DNSMAP tool on Backtrack Linux ?

 

Step 1: Open the DNSMAP Tool on Backtrack

There are multiple ways to open the DNSMAP tool over the Backtrack:

a. Using GUI Menu:  Go to Menu Bar and Click on Applications –> Backtrack –> Information Gathering –> Network Analysis –> DNS Analysis –> DNSMAP

 

b. Using Terminal: Run the below command in terminal

 

cd /pentest/enumeration/dns/dnsmap/ 

Step 2: Select the Target and Start the Scan

Say we want to gather information regarding Google. In order to run the DNSMAP we have to run the below command @ DNSMAP:

 

./dnsmap google.com

When you press the enter button you will see results similar to these screenshots:

 

DNSMAP Tutorial  – 1

DNSMAP Tutorial – 2

DNSMAP Tutorial – 3

 

 

You can see above that DNSMAP has scanned all the sub domains of Google along with all A records i.e. IP address of Google sub domains.

 

Now the above was the simplest way of using DNSMAP. In order to perform deeper searches there are several advanced options available in DNSMAP tool which are listed below :

 

 

-w <wordlist-file>
Input file to use for brute force

-r <regular-results-file>
Export results as text format

-c <csv-results-file>
Save files as csv format

-d <delay-millisecs>
Maximum delay (in ms) between 2 DNS lookups(default: 10 ms)

-i <ips-to-ignore>
Useful if you’re obtaining false positives