SpiderFoot
SpiderFoot is an open source intelligence automation tool. Its goal is to automate the process of gathering intelligence about a given target.
Purpose
There are three main areas where SpiderFoot can be useful:
If you are a pen-tester, SpiderFoot will automate the reconnaissance stage of the test, giving you a rich set of data to help you pin-point areas of focus for the test.
Understand what your network/organization is openly exposing to the outside world. Such information in the wrong hands could be a significant risk.
SpiderFoot can also be used to gather threat intelligence about suspected malicious IPs you might be seeing in your logs or have obtained via threat intelligence data feeds.