If the internet is compared to a large city, the visible part consists of main streets and side alleys that host official company websites, while the backyards, basements, and service entrances are where maintenance staff and potential intruders move. Shodan specializes in exploring exactly these hidden areas by indexing devices instead of web pages.
Unlike conventional search engines such as Google that crawl HTML content, Shodan catalogs internet-connected hardware including servers, IP cameras, databases, routers, administration panels, and IoT equipment. When administrators leave such systems exposed, analysts can discover valuable information about a company’s infrastructure.
1. Search by company domain
The simplest method uses the filter hostname:company.com. Results often reveal forgotten development, VPN, test, and API endpoints such as dev.company.com, vpn.company.com, test.company.com, and api.company.com.
2. Search by SSL certificates
The query ssl:"company.com" locates certificates that mention the target domain and frequently surfaces additional subdomains including jenkins.company.com, internal-api.company.com, and staging.company.com.
3. Search by ASN
Companies that own IP address blocks usually possess an ASN (Autonomous System Number). The filter asn:ASXXXX returns every device registered to that network, exposing servers, routers, and sometimes cameras.
4. Search by IP range
When the exact network block is known, the filter net:192.168.10.0/24 lists all devices inside the range, potentially revealing VPN services, SSH ports, Docker, Kubernetes, GitLab instances, and even internal databases.
5. Search for development infrastructure
Developers commonly use keywords such as dev, stage, staging, test, qa, beta, and internal. Queries like hostname:dev or hostname:staging can uncover unprotected development and staging environments.
6. Search for administration panels
Filters such as title:"Jenkins", title:"Grafana", and title:"Kibana" locate continuous-integration systems, monitoring dashboards, and other operational tools that sometimes remain accessible with default credentials.
7. Search for databases
Port-based queries including port:27017, port:6379, and port:9200 identify MongoDB, Redis, and Elasticsearch instances. Adding an organization filter can tie these services to the target company.
8–10. Cloud, organization, and IoT searches
Additional techniques cover cloud-hosted Docker and Kubernetes APIs, organization-name searches with org:"Company Name", and queries that surface corporate webcams, industrial controllers, and building-automation systems.
A practical five-step workflow combines hostname, SSL, organization, development-keyword, and service-title searches. In one documented case the search sequence led directly to an unprotected jenkins.dev.company.com instance containing CI pipelines, source repositories, and deployment keys.
Shodan does not exploit or attack any system; it merely displays services that are already reachable from the public internet. The most frequent reasons for exposure remain human error: forgotten test servers, temporary development environments, incorrectly configured firewalls, and rushed deployments that leave ports open.


