Explore basic web application security vulnerabilities and their prevention in this code::dive 2018 conference talk. Dive into SQL Injection, Cross-Site Scripting (XSS), and Cross-Site Request Forgery (CSRF) through live demonstrations and real-world examples. Learn how to detect, exploit, and fix these common security issues using a Java-based web application built with Spring Boot. Witness practical hacking techniques, including authentication bypass, database content retrieval, session hijacking, and unauthorized actions. Gain insights into effective protection methods such as parameter binding, encoding, and double submit cookies. Suitable for developers with basic programming knowledge in any language, this hands-on lecture provides essential skills for building more secure web applications.