Do you know SSRF

An interesting article on Server Side Request Forgery (SSRF):

In this attack, specific payloads for different ports are crafted by the attacker and sent to the server. By analyzing the errors or the time-delays in different responses for different ports, the attacker can figure out the status of the ports open on the server. And while exploiting SSRF, the attacker’s machine is not directly interacting with the target server, the vulnerable server is doing all the dirty work for the attacker.

See more at http://niiconsulting.com/checkmate/2015/04/server-side-request-forgery-ssrf.