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OSINT Basics

OSINT Basics

OSINT means Open Source Intelligence.

It is the process of collecting and analyzing information from publicly available sources.

OSINT is used in cybersecurity, investigations, research, and threat intelligence.

What Counts as OSINT?

OSINT uses information from sources that are publicly accessible or legally available.

Examples:

  • websites
  • search engines
  • social media
  • public documents
  • public code repositories
  • public DNS records
  • news articles
  • company websites

Why OSINT Matters

OSINT can help with:

  • understanding an organization
  • finding public attack surface
  • discovering technology footprints
  • locating exposed data
  • supporting investigations
  • mapping relationships between people, domains, and infrastructure

Common OSINT Targets

  • domain names
  • email formats
  • usernames
  • subdomains
  • documents
  • metadata
  • leaked public information
  • public IP information
  • social media profiles

Common OSINT Techniques

Search Engine Research

Search engines can reveal:

  • documents
  • cached pages
  • public endpoints
  • exposed files
  • company details

Domain Research

You can examine:

  • WHOIS data
  • DNS records
  • subdomains
  • hosting information

Social Media Research

Public social media posts can reveal:

  • job roles
  • tools used
  • project details
  • locations
  • relationships between accounts

Public Code Research

Public code repositories may reveal:

  • credentials accidentally committed
  • internal names
  • development tools
  • project structure
  • exposed endpoints

Useful OSINT Data Sources

  • Google
  • Bing
  • WHOIS
  • DNS tools
  • GitHub
  • LinkedIn
  • Shodan
  • VirusTotal
  • public company websites
  • archived web pages

Important Concepts

Metadata

Metadata is data about data.

Examples:

  • author name
  • file creation date
  • software used
  • location information
  • document properties

Footprint

A footprint is the digital trace a person or organization leaves online.

Correlation

Correlation means connecting multiple small pieces of public data to build a bigger picture.

Good OSINT Habits

  • use legal and ethical sources only
  • verify information before trusting it
  • avoid jumping to conclusions
  • record sources carefully
  • respect privacy and laws
  • focus on public information only

OSINT in Cybersecurity

In cybersecurity, OSINT can help with:

  • reconnaissance
  • threat intelligence
  • exposure checking
  • attack surface discovery
  • awareness of public information leaks

Final Note

OSINT is powerful because small public details can combine into important insight.

The skill is not just collecting data.
The skill is understanding what the data means.