OSINT

Open Source Intelligence, gathering information from publicly available sources to solve challenges. Involves search engines, social media, geolocation, and metadata analysis.

Google Dorking
Geolocation
Metadata
Shodan
Social Media

What is OSINT?

Open-Source Intelligence (OSINT) is, very simply put, just collecting and analyzing data from public sources.

In the context of Capture The Flag (CTF) competitions, it is like being a digital detective. You only have crumbs of information and must use that to find a hidden flag. It often manifests itself in finding the origin of a picture. For example, something like, in what town does this cat reside in?

A cat sitting outdoors, used as an example geolocation challenge
Image credit: Bellingcat Open Source Challenge

Beginner’s Guide to OSINT

Getting started with OSINT is more about developing a curious mindset than mastering complex tools. Here are some essential tips to help you get started:

Google Dorking

Use advanced search operators to filter search engine results. For example, using site:example.com filetype:pdf will restrict your search strictly to PDF files hosted on example.com.

Reverse Image Searching

Tools like Google Images, Yandex, or TinEye can help you determine where an image has appeared online previously, or identify specific landmarks, objects, and text within the image.

Username Checking

Cross-referencing usernames across multiple platforms (e.g., using tools like Sherlock or Namechk) can build a comprehensive profile of a target and uncover hidden connections.

Metadata Analysis

Files often contain hidden information (metadata) such as GPS coordinates in photographs, author names, or creation dates in documents. Use online tools or command-line programs to extract this hidden data.

Resources & Tools

OSINT Framework

A massive collection of OSINT tools categorized by their specific use case.

Google Hacking Database

An extensive archive of Google Dorks that can reveal sensitive information.

Sherlock

A command-line tool to hunt down social media accounts by username across a vast number of networks.

Namechk

An online tool to check the availability of a username across dozens of social networks.

Yandex Reverse Image Search

A powerful reverse image search engine, often considered one of the best for finding image origins.

TinEye

A popular reverse image search engine that tracks where and how an image has appeared online.