Security Flaws XSS, CSRF, SQL Injection, HTML Injection

This article reviews common web application vulnerabilities—Cross-Site Scripting (XSS), Cross-Site Request Forgery (CSRF), SQL Injection, and HTML Injection—citing historical compromises and explaining why these flaws persist. It highlights misconceptions (e.g., XSS is 'just popups', SQLi is only for reading data), demonstrates how attacks can be hidden or encoded, and recommends allowlist-first input validation and use of framework protections to prevent code injection.