Shodan

Shodan is a search engine for internet-connected devices, indexing servers, routers, IoT devices, industrial control systems, webcams, and databases. Unlike traditional search engines that index websites, Shodan scans the internet for open ports, services, and banners, providing visibility into what is actually exposed to the public internet. Security professionals use Shodan for attack surface discovery, vulnerability identification, and threat hunting. The platform offers a web interface, a command-line interface, and REST and Streaming APIs for programmatic access. Shodan also provides network monitoring with alerts for new open ports and services, historical data on IP addresses, and integration with security tools. Shodan's data has exposed significant security issues across the internet, including unprotected webcams, exposed databases, and vulnerable remote desktop services. Researchers and government officials have used the platform to identify large-scale exposures, such as over 1.8 million RDP servers and 1.6 million VNC instances reachable from the public internet, with hundreds of VNC servers allowing direct access to industrial control panels without authentication. The platform is also used to find industrial control systems exposed to the public internet, which can pose operational and safety risks. Access to Shodan is tiered. A free account allows basic searches with limited results. A one-time Membership provides more features, while subscription plans offer higher query limits, access to restricted filters like vulnerability and tag searches, and expanded monitoring capabilities.