how to approach OSINT challenges.

first steps for any OSINT challenge

1. 1.read the challenge description extremely carefully. extract every piece of information: names, usernames, dates, locations, organizations, email formats. each detail is a potential pivot point.
2. 2.identify what type of OSINT you're doing: finding a person, a location, a domain, or an organization. the type determines the tools and search strategy.
3. 3.search Google with exact quotes and site: operators. "username" site:twitter.com, "email@domain" — narrow results with operators before broad searching.
4. 4.check image metadata with exiftool — GPS coordinates, camera model, original filename, timestamps. CTF images often have location data deliberately left in.
5. 5.don't over-tool too early. a well-crafted Google search finds most OSINT flags faster than running automated tools.

common challenge types and approach

• geolocationgiven an image, find the location. look for street signs, building architecture, vegetation, sun angle, shadows, Google Street View-able landmarks. use reverse image search first, then analyze visual clues.
• username / person searchgiven a username, find accounts on other platforms. use Sherlock to search 300+ sites automatically. check known platforms manually (GitHub, Twitter/X, Reddit, LinkedIn). look for cross-platform connections.
• domain / organization researchWHOIS lookup for registration info. DNS records (dig, nslookup) for subdomains and mail servers. Shodan for exposed services. certificates (crt.sh) for subdomain enumeration.
• social media investigationread all posts, check followers/following, look for location check-ins, tagged photos, and connections. use the Wayback Machine for deleted posts and old profile versions.
• image reverse searchGoogle Images, TinEye, Yandex Images (often better for European/Asian landmarks). try cropping to the most distinctive element of the image for better matches.
• email / account enumerationcheck haveibeenpwned.com for breach data. hunter.io for email format patterns. LinkedIn for professional context. GitHub for email leaks in commit history.

useful tools

• Sherlock — searches 300+ social media sites for a given username. run: sherlock username.
• exiftool — extracts metadata from images including GPS coordinates. run: exiftool image.jpg.
• Wayback Machine — archive.org — view old versions of websites and deleted pages. useful for finding removed content.
• Shodan — search engine for internet-connected devices. find exposed services, banners, and IP intelligence.
• crt.sh — certificate transparency logs. find subdomains by searching for the root domain. often reveals internal infrastructure.
• Google Dorks — site:, filetype:, inurl:, intitle:, "exact phrase" operators dramatically narrow search results.