Hướng dẫn OSINT từng bước

Finding an email address from a name is one of the most common OSINT questions — for journalists chasing sources, recruiters reaching candidates, sales teams prospecting, and individuals reconnecting with lost contacts. The accuracy you can expect ranges from 50-90% depending on how much public footprint the target has.

Phone-number verification answers three questions: (1) is this number real and active?, (2) who or what is on the other end?, (3) is it likely a scam? You can answer all three with public OSINT — no calling required.

Reverse image search answers: where else has this image appeared? It's the foundation of misinformation debunking, plagiarism detection, photo verification, and finding original sources. Modern reverse image search combines visual-similarity matching with EXIF-data analysis and AI-deepfake detection.

If you've used the internet for more than five years, statistically one of your passwords has appeared in at least one data breach. The question isn't 'have any of mine leaked' — it's 'which ones, and have I changed them since?' This guide shows how to check safely using k-anonymity, so you never have to send your real password to a third-party service.

Crypto-wallet investigation is the financial-crime side of OSINT — useful for journalists tracking ransomware payouts, fraud teams investigating chargebacks, and individuals trying to recover stolen funds. The blockchain is fully public, but tooling matters: raw blockchain explorers show transactions, while clustering tools reveal which addresses likely belong to the same entity.

Finding someone's social-media presence is core SOCMINT (Social Media Intelligence). The best approach combines three angles: username search (find handle across platforms), name search (find profiles attached to a name), and photo search (find profiles using the same photo). Combining all three gives 80-95% completeness for an average target.