Are WAF and API Gateway Enough? Is API Security Necessary Against Modern Threats?
APIs have become one of the main building blocks of communication between software systems in today’s rapidly digitizing world. Contemporary software approaches such as application modernization, microservice architectures, and multi-platform strategies place APIs at the center. This growth brings not only operational advantages but also new security risks that must be carefully addressed. In this context, many organizations are asking themselves a fundamental question: If solutions such as WAF or API Gateway are already in use, is there a need for an additional API security solution?
At first glance, this question may seem reasonable and logical. WAF (Web Application Firewall) systems are an important defense layer that protects against known attack types by analyzing HTTP traffic. On the other hand, API Gateway solutions play a crucial role in managing API traffic through functions such as routing API requests, load balancing, rate limiting, and basic authentication. However, while these solutions protect the outer perimeter of the system, they may be insufficient in detecting and blocking threats specific to the API architecture. Many real threats are hidden in the content of API traffic, user roles, and business logic. Therefore, relying solely on WAF or gateway can create serious blind spots in your security architecture.
Today’s API attacks are not limited to superficial threats. Attackers are now focused on deciphering the system’s operational logic and exploiting vulnerabilities within that logic. Many attacks are carried out not only through the client interface but also through direct calls to API endpoints. For example, manually adding a field such as isAdmin: true, which is not visible on the client side, allows a user to elevate themselves to an unauthorized administrator position. Similarly, sequential requests can be made with different user identities to test cross-user data access. Most of these types of attacks result in HTTP 200 response codes, so they are considered “harmless” by signature-based systems. However, in reality, the internal integrity of the system has been compromised.
API documentation can also become a powerful guide in the hands of attackers. By examining documents such as Swagger or OpenAPI, the entire endpoint map of the system can be mapped out. Thus, the attacker does not merely engage in random attempts but can develop a systematic and methodical attack plan. All these processes push the limits of traditional security solutions, as these solutions lack the ability to understand context, interpret data relationships, and analyze behavior patterns.
API security is not merely a traffic management task; it is a discipline that involves layered analysis, including data-level authorization, user role tracking, and detection of abnormal behavior. Modern API security approaches must evaluate each call not just on the surface but within its context. Structures that can answer questions such as who the user is, what they are trying to access, which data fields they are touching, and how the system responds to this can provide real protection. Otherwise, the system is reduced to a security solution that merely filters out bad data from the outside, which is insufficient.
Today, WAF, gateways, authentication systems, and API security solutions should be part of a complementary, integrated security architecture. When these structures work together, they provide effective defense. However, if any one of them is missing, weak points may appear in the defense line. A structure that cannot detect API-specific threats remains vulnerable to attacks, which can damage the system as a whole. This is because attackers target not only external vulnerabilities but also internal misconfigurations, insufficient authorization controls, and data redundancy.
In particular, data-level authorization controls, role-based access restrictions, and behavior-based anomaly analysis are now essential for security. Systems capable of performing such analyses not only detect attacks but also provide proactive protection against invisible vulnerabilities. This approach is not only a technical necessity but also critically important from the perspectives of legal regulations and corporate reputation.
Solutions that address API security not only at the request level but also at the content and context levels make systems much more prepared for today’s and tomorrow’s threats. It is no longer enough to just lock the front door; you need to know who is entering, what they are accessing, what data they are interacting with, and how they are behaving. Since modern attacks are complex, targeted, and layered, the defense must be equally comprehensive.
