Web Security for Front-End Developers: XSS, CSRF, and CORS
Security is no longer just a backend concern. With the growing complexity of front-end applications, every front-end developer must understand key security vulnerabilities and how to safeguard against them. Let's explore three critical areas: Cross-Site Scripting (XSS) , Cross-Site Request Forgery (CSRF) , and Cross-Origin Resource Sharing (CORS). 1. Cross-Site Scripting (XSS) What it is: XSS occurs when malicious scripts are injected into web pages viewed by other users. This allows attackers to execute arbitrary code in the browser, steal cookies, or hijack sessions. Types of XSS: Stored XSS Reflected XSS DOM-based XSS Mitigation: Escape user input before rendering it in the DOM. Use frameworks/libraries that auto-escape (e.g., React, Angular). Sanitize inputs on both client and server side. // Avoid element.innerHTML = userInput; // Safe element.textContent = userInput; 2. Cross-Site Request Forgery (CSRF) What it is: C...