Critical Appreciation: Theharvester: Email Harvesting Throughout Year

You might have harvested many things upto now but what we are going to harvest today is something bad :)

Requirements:

A Linux box (I'm using Kali Linux)
theharvester program (already available in Kali Linux)

So what does theharvester harvest? Well it harvests email addresses. theharvester is an Information gathering tool. If you want a list of emails to spam you can get that easily from theharvester tool and go on Spamming (I'm joking its illegal). It's a security tool that helps you in pentesting an organization (as always it can be used for evil as well). You can gather emails from an organization and look for potential victims to attack or use brute-force techniques to get their passwords or Social Engineer them into doing something that will let you compromise some or all systems in the organization. Uhh there are so many things that you can do when you have access to someone's email address.

OK stop talking and start doing.

Fire up a terminal in your kali box and type this command:

theharvester -d hotmail.com -l 50 -b google

In a small amount of time you'll see your terminal flooded with 200 hotmail.com email address. What does this command mean?

theharvester is the tool name that we are using
-d <domain_name> specifies the domain (or website) who's email addresses we're looking for, in our case it was hotmail.com
-l <number> specifies the number of results that we want in the output, I limited it to 50
-b <source> specifies the source on which to look for email addresses, I specified google as the source

Besides google we can specify any of the follow as source:
google, googleCSE, bing, bingapi, pgp, linkedin, google-profiles, people123, jigsaw, twitter, googleplus, all
Here the last entry all means look in every available source.

Let's say you wanted to look in every available source they you should specify the following command:

theharvester -d hotmail.com -b all

-f is another great flag which can be utilized to save the output in case we want to SPAM them later (just kidding) or for other reasons (I'm thinking positive). -f flag saves the result in html or xml format. Let's do just that:

theharvester -d gmail.com -l 50 -b google -f emailaddresses.html

here -f flag is followed by the location where we want to store the file and the name of file, in our case we stored it in our pwd (present working directory) with the name emailaddresses.html.