Content Security Policy

Content Security Policy (CSP) is a web security standard that helps prevent cross-site scripting (XSS), clickjacking, and other code injection attacks by allowing website administrators to specify which sources of content are allowed to be loaded by the browser. It works by defining a set of directives in HTTP headers or meta tags that restrict where resources like scripts, styles, images, and fonts can be fetched from, thereby reducing the risk of malicious content execution.

Also known as: CSP, Content-Security-Policy, Content Security, Web Security Policy, Security Headers

Why learn Content Security Policy?

Developers should learn and implement CSP to enhance the security of web applications, especially in environments handling sensitive user data or prone to XSS vulnerabilities. It is crucial for compliance with security standards like OWASP Top 10 and is widely used in modern web development to mitigate common attack vectors, making it essential for building robust, secure websites and applications.

Learning Resources

• docs: MDN Web Docs: Content Security Policy
• tutorial: Google Web Fundamentals: Content Security Policy
• docs: OWASP Content Security Policy Cheat Sheet
• tool: CSP Evaluator by Google