Shodan
The Search Engine for Internet-Connected Devices
Shodan is a search engine that lets users find specific types of computers connected to the internet using a variety of filters. Unlike traditional search engines that crawl websites, Shodan scans ports and services across the internet, providing visibility into internet-connected devices.
What is Shodan?
Shodan is often described as "Google for hackers" or "the scariest search engine on the internet," but these descriptions don't fully capture its legitimate uses for security professionals, researchers, and OSINT analysts. At its core, Shodan is a search engine for internet-connected devices - from webcams and routers to industrial control systems and servers.
Unlike traditional search engines that index web content, Shodan scans the internet for devices, collects information about what's connected, what services they're running, and potential vulnerabilities they might have. This makes it an invaluable tool for security assessments, network monitoring, and open source intelligence gathering.
How Shodan Works
Shodan works by scanning the entire IPv4 address space (and increasingly IPv6) on various ports, sending requests to these ports, and analyzing the responses. When a device responds, Shodan records information such as:
- •The device's IP address and geographic location
- •What organization owns the IP address
- •What services and ports are open
- •What software is running and its version
- •Banner information that might reveal additional details
This information is then indexed and made searchable through Shodan's web interface, API, and command-line tools.
Ethical Considerations
While Shodan is a powerful tool for legitimate security research and OSINT investigations, it's important to use it ethically and legally:
- •Respect Privacy: Just because a device is exposed doesn't mean you have permission to access it beyond what's publicly visible.
- •Legal Boundaries: Always operate within the legal framework of your jurisdiction. Unauthorized access to systems is illegal in most countries.
- •Responsible Disclosure: If you discover vulnerable systems, consider responsible disclosure to the affected organizations.
Related Resources
Learn advanced techniques for leveraging Shodan in your OSINT investigations, including search strategies, data analysis, and integration with other tools.
Explore Censys, another internet scanning search engine that complements Shodan with different scanning methodologies and data points.
Learn how to craft effective search queries across various OSINT platforms, including Shodan, Google, and specialized search engines.