CompTIA SecurityX (CAS-005)Security ArchitectureMedium

A security architect is evaluating a new cloud-native application that exposes several APIs to external partners. The architect needs to protect these APIs from common web-based attacks such as SQL injection, cross-site scripting (XSS), and malicious bots, while also providing rate limiting and API security analytics. Which security control would be most effective for this purpose?

  1. ANetwork Access Control List (NACL)
  2. BSecurity Group
  3. CVirtual Private Cloud (VPC)
  4. DWeb Application Firewall (WAF)
Show answer & explanation

Correct answer: D. Web Application Firewall (WAF)

A Web Application Firewall (WAF) operates at the application layer and is specifically designed to protect web applications and APIs from common web-based attacks like SQL injection and XSS. Modern WAFs also offer features like rate limiting and API security analytics.

Why the other options are wrong

  • A. NACLs operate at the subnet level and provide stateless packet filtering based on IP and port, not protection against application-layer attacks.
  • B. Security Groups provide stateful packet filtering at the instance level, similar to a host firewall, but they do not understand application-layer attack patterns.
  • C. A VPC provides network isolation in the cloud but does not offer application-layer protection against specific web attacks.

Web Application Firewall (WAF)

A Web Application Firewall (WAF) is a security solution that monitors and filters HTTP/HTTPS traffic between a web application and the Internet. It protects web applications from various attacks, including cross-site scripting (XSS), SQL injection, and other OWASP Top 10 vulnerabilities.

  • Operates at the application layer (Layer 7 of OSI model).
  • Protects against common web-based attacks.
  • Can enforce security policies, perform rate limiting, and provide API security.
  • Can be network-based, host-based, or cloud-based.

Memory trick: WAF Watches Web Attacks Fiercely.

More Security Architecture questions