Some Search Engines Used by Security Researchers

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Security professionals often need to quickly search and correlate data during OSINT (Open-source intelligence), reconnaissance, vulnerability detection, network security breaches, and more. Fortunately, there are quite a few interesting and useful search engines in their arsenal. I will try to do a simple explanation as possible.

1. Shodan is a network security monitoring system and search engine that indexes data from any type of electronic device that has ever been connected to the Internet.
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2. Censys is similar to Shodan in that it tracks every device available on the Internet and provides data and reports in the form of a search engine on how devices, websites, and certificates are set up. Censys is a free search engine that was originally released in October 2015 by researchers from the University of Michigan and is powered by the world's biggest search engine Google.
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3. GreyNoise is the exact opposite of Shodan and Censys. This system tracks those who scan the Internet using the aforementioned scanners. GreyNoise Intelligence was founded by Andrew Morris in 2017 with the goal of analyzing Internet background noise to remove pointless security alerts
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4. Hunter is a search engine that helps you find all email addresses belonging to a domain or organization.

5. WiGLE is a search engine for displaying wireless networks.WIGLE (Wireless Geographical Logging Engine) logs/ collects Wifi hotspots all over the internet. The company Wigle has started in 2001 collected 349 million Wifi Hotspots which are running over the internet. Users can register on the site and upload their data. Wigle uses 802.11 wireless networks to collect location. 802.11 is a standard protocol used to connect Wireless devices on the internet. 802.11 operates 2.4 GHz & 5 GHz band worldwide. Wigle collects GPS coordinates, MAC addresses, BSSID & encryption used in wireless hotspot security.
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6. Have you ever wanted to search for websites based on their source code? Well, there is a search engine that indexes the source codes, and that's https://publicwww.com/.

7. Pipl is a system designed to search for information about a specific person.

I hope you learn something. Thanks