Web Security Basics Every Full-Stack Developer Should Know

Web security involves protecting applications, user data, and infrastructure from malicious actors who exploit vulnerabilities beyond normal usage patterns. Full-stack developers must safeguard assets including user accounts, passwords, authentication tokens, personal information, API endpoints, and databases. Security risks can surface at every layer of a web application, from the frontend and network to the backend API, authentication middleware, and database. Common threats include cross-site scripting (XSS), injection attacks, broken access controls, insecure direct object references (IDOR), and denial-of-service attacks. Understanding how data travels through each layer of an application is a foundational step toward identifying and addressing these risks.