Securing Web Apps with Domain Isolation and Delegation

When a single subdomain is compromised, your entire primary domain and its sensitive user cookies can be put at risk. Security-conscious organizations prevent this by isolating low-priority services and delegating untrusted content to separate, sandboxed domains. This text-only course teaches you how to design a robust domain segregation strategy to limit the impact of web attacks like Cross-Site Scripting (XSS) and Cross-Site Request Forgery (CSRF). You will discover how to protect your brand's core assets by strategically offloading secondary services. What you'll learn: - Understand the security risks of hosting mixed-trust applications on a single primary domain - Implement domain isolation and sandboxing strategies to minimize the blast radius of web vulnerabilities - Configure SameSite cookie attributes and CORS policies to prevent unauthorized cross-domain access - Set up delegated subdomains with tailored Content Security Policies (CSP) and DNS records - Manage third-party integrations and user-generated content safely using separate domain structures - Analyze real-world scenarios where domain segregation prevents total system compromise You will start with foundational web security concepts, exploring how browsers handle cookies and origin boundaries. From there, you will progress to practical architecture patterns for delegating domains and securing secondary services. This course is designed for beginner web developers, system administrators, and security enthusiasts looking to build a strong foundation in secure web architecture. No prior security experience is required. Begin reading today to build a more resilient and secure web infrastructure.