26/07/2016
Sometimes, we don't have a specific target in mind, but rather we are simply looking for vulnerable and easy-to-hack targets anywhere on the planet. Wouldn't be great if we had a search engine like Google that could help us find these targets? Well, we do, and it's called Shodan!
What Is Shodan?
Some have described Shodan as a search engine for hackers, and have even called it "the world's most dangerous search engine". It was developed byJohn Matherly in 2009, and unlike other search engines, it looks for specific information that can be invaluable to hackers.
Shodan pulls service banners (see my tutorial on fingerprinting web servers for more on banners) from servers and devices on the web, mostly port 80, but also ports 21 (ftp), 22 (SSH), 23 (telnet), 161 (SNMP), and 5060 (SIP).
What Can Shodan Show Us?
Since almost every new device now has a web interface (maybe even your refrigerator) to ease remote management, we can access innumerable web-enabled servers, network devices, home security systems, etc.
Shodan can find us webcams, traffic signals, video projectors, routers, home heating systems, and SCADA systems that, for instance, control nuclear power plants and electrical grids. If it has a web interface, Shodan can find it!
Although many of these systems communicate over port 80 using HTTP, many use telnet or other protocols over other ports. Keep that in mind when trying to connect to them.
Now let's take a look at this fascinating and nefarious search engine!
1) Log in to Shodan
First, we need to log in to shodanhq.com. Although you can use Shodan without logging in, Shodan restricts some of its capabilities to only logged-in users.