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How to Use Shodan Step by Step | FreeCourse Cybersecurity · OSINT · Pentesting How to Use ShodanStep by Step Shodan is the world's most powerful search engine for internet-connected devices. Learn how to use it from scratch — web interface, CLI, advanced filters, Shodan Monitor, and bug bounty integration — with real hands-on examples. ⏱ Read time: 11 min 🔐 Level: Beginner → Advanced ✦ Hands-on Guide What is Shodan? Created by John Matherly in 2009, Shodan is often described as "Google for hackers" — but that barely scratches the surface. While Google indexes web page content, Shodan continuously scans the entire IPv4 address space and indexes the metadata of every internet-connected device it finds: servers, routers, webcams, industrial control systems, databases, smart TVs, satellites, and more. For penetration testers, bug bounty hunters, and security researchers, Shodan is an irreplaceable reconnaissance tool. It allows you to discover exposed assets passively — without sending a single packet to your target — making it ideal even for programs that restrict aggressive scanning. ⚖️ Legal disclaimer Shodan itself is a legal and legitimate tool. However, using the information it provides to access systems without authorization is illegal. Always operate within the scope of a bug bounty program or with explicit written permission from the asset owner. This guide is for educational and authorized security testing purposes only. Step 1 — Create Your Account Head to shodan.io and register for a free account. A free account gives you limited search results (2 pages max) and access to basic filters. For serious pentesting work, the Membership plan ($49 one-time) is the best value — it unlocks the full CLI, unlimited filters, and API access. 🆓 Free Account 2 pages of results per query, basic filters, limited API calls. Good for exploration and learning. 💳 Membership ($49) Full CLI access, all filters, 1 query credit/month, export results, Shodan Monitor (5 IPs). Best for bug bounty hunters. 🏢 Small Business More API credits, team features, advanced monitoring, bulk data export for professional security teams. 🔑 API Key Available in your dashboard under "Account". Required for the CLI and all programmatic access. Keep it private. Step 2 — The Web Interface Once logged in, the search bar at shodan.io is your starting point. Type any keyword — a product name, a banner string, a CVE — and Shodan returns every device on the internet that matches. Your first search Try typing nginx in the search bar. You will instantly see millions of servers worldwide running Nginx, with their IP address, country, open ports, banner data, and hostnames. 💡 Understanding a Shodan result Each result card shows: the IP address, the open ports, the banner (raw response from the service), the country and city, the organization (ISP or company), and detected vulnerabilities (CVEs) if your plan includes them. Click any result to see the full host profile. Key sections of the dashboard 🗺Maps — Visualize search results on an interactive world map. Limited to 1,000 results at a time. Zoom in to drill into a specific region. 📊Explore — Browse curated searches and the most popular queries from the community. Great for inspiration. 🖼Images — A gallery of screenshots captured from exposed devices via VNC, RDP, RTSP, webcams, and X Windows. Search with has_screenshot:true. 💣Exploits — A search engine that cross-references exposed devices with known CVEs and exploits from multiple databases simultaneously. 📡Monitor — Track your own assets in real time. Set alerts when new ports open or services change (covered in depth below). Step 3 — Master the Search Filters Raw keyword searches return too many results to be useful. Filters are what make Shodan truly powerful. They follow the syntax filter:value and can be combined freely. Filter Description Example port:Filter by specific port numberport:22 product:Filter by software/product nameproduct:Apache version:Filter by software versionversion:2.4.49 os:Filter by operating systemos:"Windows Server 2019" country:Filter by 2-letter country codecountry:FR city:Filter by city namecity:Paris org:Filter by organization / ISP nameorg:"Amazon" hostname:Filter by hostname or domainhostname:".gov" net:Filter by IP range (CIDR)net:192.168.0.0/24 http.title:Filter by HTML page titlehttp.title:"Login" http.status:Filter by HTTP status codehttp.status:200 ssl.cert.subject.cn:Filter by SSL certificate CNssl.cert.subject.cn:"example.com" vuln:Filter by CVE number (paid)vuln:CVE-2021-44228 has_screenshot:Only return hosts with a screenshothas_screenshot:true before: / after:Filter by scan dateafter:01/01/2024 Combining filters — real examples Find exposed Apache 2.4.49 servers (CVE-2021-41773 — Path Traversal) product:Apache version:2.4.49 Find MongoDB databases with no authentication in France product:MongoDB country:FR port:27017 Find exposed Elasticsearch instances globally product:Elasticsearch port:9200 http.status:200 Find login panels for a specific organization org:"Target Corp" http.title:"Login" Find webcams with open access (no auth) has_screenshot:true product:webcam http.title:"Live View" Find exposed RDP servers in the US port:3389 country:US os:"Windows" Find all assets on a specific IP range net:203.0.113.0/24 Find Log4Shell vulnerable hosts (CVE-2021-44228) vuln:CVE-2021-44228 Step 4 — Install and Use the Shodan CLI The Shodan CLI (Command Line Interface) lets you run Shodan queries directly from your terminal, automate searches, and pipe results into other tools. It is a must-have for efficient pentesting workflows. Installation Install Shodan CLI bash # Install via pip (Python required) pip3 install shodan # Initialize with your API key shodan init YOUR_API_KEY_HERE # Verify installation shodan info Query credits available: 100 Scan credits available: 100 Essential CLI commands Basic search bash # Simple keyword search (no credits consumed) shodan search nginx # Search with filters (consumes 1 query credit) shodan search "product:Apache country:US port:443" # Limit results and select specific fields shodan search --fields ip_str,port,org,hostnames --limit 100 "product:nginx" # Count total results without displaying them shodan count "port:22 country:DE" 1248392 Host lookup bash # Get complete info on a specific IP address shodan host 8.8.8.8 # Output in JSON format (for scripting) shodan host 8.8.8.8 --format json # Resolve a domain to IPs via Shodan DNS shodan domain example.com Statistics and data export bash # Get statistics about a search query shodan stats --facets country,org,port "product:Redis" # Download results to a file (consumes credits) shodan download output.json.gz "product:MySQL port:3306" # Parse the downloaded file shodan parse --fields ip_str,port,org output.json.gz # Convert to CSV for spreadsheet analysis shodan convert output.json.gz output.csv Monitor alerts via CLI bash # Create an alert for an IP range shodan alert create "My Network" 203.0.113.0/24 # List all active alerts shodan alert list # Get triggered notifications shodan alert info ALERT_ID Step 5 — Shodan Monitor: Watch Your Attack Surface Shodan Monitor is a real-time tracking feature that continuously watches a set of IP addresses or CIDR ranges and alerts you whenever something changes — a new port opens, a service changes, or a new vulnerability is detected. This is invaluable both for defenders (monitoring their own infrastructure) and for bug bounty hunters (tracking a target's new assets as they appear). 1 Set up a new alert Go to monitor.shodan.io → click "Add Network" → enter your IP or CIDR range (e.g., 203.0.113.0/24) → give it a name. With the Membership plan you can monitor up to 16 IPs for free. 2 Configure notification triggers Click on the alert → go to "Triggers". You can set alerts for: new open ports, new services, new vulnerabilities (CVEs), SSL certificate changes, new malware detections, or any custom filter. Useful trigger examples • Alert when port 22 (SSH) or 3389 (RDP) becomes open • Alert when a new CVE is detected on your network • Alert when an SSL certificate expires or changes • Alert when a new host appears in the monitored range 3 Connect notifications Shodan Monitor can send alerts via email, Slack webhook, or via the API. For bug bounty hunters, connecting it to a Slack channel is the most efficient setup — you get notified in real time when a new asset appears. Step 6 — Shodan for Bug Bounty Recon Shodan integrates seamlessly into a bug bounty recon workflow. Here is how to use it alongside popular tools to build a comprehensive picture of a target's attack surface. Enumerate all assets of a target organization Org-based recon workflow bash # 1. Find all IPs belonging to a target org shodan search --fields ip_str,port,hostname org:"Target Company" # 2. Find all subdomains via SSL certificates shodan search --fields ip_str,port,ssl.cert.subject.cn \ 'ssl.cert.subject.cn:"*.targetcompany.com"' # 3. Find login panels (juicy targets) shodan search 'org:"Target Company" http.title:"Login"' # 4. Find exposed admin interfaces shodan search 'org:"Target Company" http.title:"Admin"' # 5. Find hosts with expired SSL certs (often forgotten assets) shodan search 'ssl.cert.expired:true org:"Target Company"' Integration with other recon tools Shodan + httpx pipeline bash # Extract all IPs and pipe into httpx for HTTP probing shodan search --fields ip_str,port org:"Target" \ | awk '{print $1":"$2}' \ | httpx -silent -status-code -title # Extract IPs and pipe into nuclei for vulnerability scanning shodan search --fields ip_str org:"Target" \ | nuclei -t technologies/ -silent Shodan Python API — quick script python #!/usr/bin/env python3 import shodan API_KEY = "YOUR_API_KEY" api = shodan.Shodan(API_KEY) # Search for exposed Jenkins instances results = api.search('http.title:"Dashboard [Jenkins]"') print(f"Total results: {results['total']}") for match in results['matches']: print(f"{match['ip_str']}:{match['port']} — {match.get('org', 'N/A')}") Step 7 — Advanced Techniques Favicon hash search Every web application has a favicon. If you hash it (using the MurmurHash algorithm), you can find all servers worldwide running the same application — even if they've changed their banners or titles. This is particularly powerful for finding forgotten or hidden instances of a target's infrastructure. Generate and search favicon hash python # Python: compute favicon hash from a URL import requests, mmh3, base64, codecs response = requests.get("https://target.com/favicon.ico") favicon = codecs.encode(response.content, "base64") hash_value = mmh3.hash(favicon) print(f"Favicon hash: {hash_value}") # Then search Shodan for this hash # http.favicon.hash:-XXXXXXX Shodan search with favicon hash bash # Example: find all servers with the Grafana favicon shodan search 'http.favicon.hash:-1028726852' # Example: find all servers with a specific app favicon shodan search 'http.favicon.hash:HASH_VALUE org:"Target"' Shodan 2000 — The retro real-time view Go to 2000.shodan.io to see a live, real-time stream of devices being indexed by Shodan at this very moment. Beyond the aesthetic, it gives you a raw sense of what Shodan is actually scanning and how much data it collects every second. Internet Exposure Observatory Available at exposure.shodan.io, this dashboard lets you see the global exposure statistics for any country or technology: how many devices are exposed, on which ports, running which software. Useful for threat intelligence and understanding the attack surface of a sector. Common Mistakes to Avoid ✕ Scanning without authorization — finding something on Shodan does not give you permission to connect to it. Always verify scope before taking any action on a target. ✕ Wasting query credits — simple keyword searches (no filters) don't consume credits. Save filters for targeted queries. Use shodan count before downloading to estimate the result size. ✕ Ignoring the "before/after" filters — Shodan data can be weeks old. Use after:01/01/2024 to ensure your results reflect the current state of a target. ✕ Forgetting SSL certificate recon — ssl.cert.subject.cn and ssl.cert.subject.org are among the most powerful filters for discovering all assets linked to a company, including subdomains and IP ranges you'd never find otherwise. ✕ Not verifying results — Shodan data is a snapshot. Always confirm with active tools (httpx, nmap, etc.) before reporting a vulnerability in a bug bounty context. Go further in cybersecurity? Access full cybersecurity courses: pentesting, OSINT, CTF challenges and more. Explore courses → Related Articles Shodan is most powerful when combined with the right knowledge. These articles will help you build a complete recon and security toolkit. 🔍 What is OSINT? The complete beginner's guide to Open Source Intelligence — the foundation of any recon workflow. 🎭 What is Social Engineering? The art of human hacking — understanding the attack vectors that go beyond technical exploitation. 🔐 Password Security Why strong passwords matter even more when your exposed services are indexed by Shodan. 🛡 Basic Pentesting Put your Shodan recon skills to practice with this hands-on TryHackMe walkthrough.

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