Same-Origin Policy & CORS
Web Fundamentals
Simple
Same-Origin Policy & CORS is a building block of "Web Fundamentals". In plain terms: html, javascript, http, cookies, sessions, apis and how web apps are built. This topic focuses specifically on same-origin policy & cors and the core ideas you need to understand it.
Technical
Technically, Same-Origin Policy & CORS involves the mechanisms, data structures and protocols that underpin web fundamentals. You will study how it is implemented, how it is configured, how it fails, and how its behavior shows up in logs, traffic or code.
Why it matters
Web apps are the largest attack surface on the internet.
Example
In a real organization, professionals working in appsec, bug bounty, web pentesting, waf tuning. rely on same-origin policy & cors to make decisions — for example, explaining an alert, hardening a system, or writing a finding in a report.
Practice idea
Build a small lab in a VM and experiment with same-origin policy & cors using the related tools below. Document what you observe.
Deep dive
Read the official documentation and relevant RFCs/standards for Same-Origin Policy & CORS. Explore edge cases, internals, and how attackers and defenders view it differently.