Securing your web APIs is both an economical and logical decision due to its widespread usage in modern applications. API security should ideally include access control, privacy regulations, and the detection and resolution of security vulnerabilities with the help of techniques like reverse engineering and vulnerability exploitation.
Developers and testers usually look into the OWASP API Security Top 10 guides for the latest updates on API security vulnerabilities and the process of testing the top 10 security threats listed in the OWASP top 10 is called OWASP Pentesting. The ease of using APIs to make a client-side app shouldn’t hide the fact that the hidden security vulnerabilities have the ability to target all the employees, clients, and partners, making risk mitigation essential.
Why is API Security important?
Since APIs are accessible from multiple locations, they contain a lot of vital information to their functioning which makes them susceptible to reverse engineering and distributed denial of service (DDoS) attacks. Beyond this, API deployment has come up strong due to the recent trends in digital transformation and its important role in mobile apps and IoT. This is why API security has the main goal of adding onto application security and assessing the impact of a hacking attempt, such as bypassing the client-side to leak data or disturb the functioning.
API security often includes that of your own and the APIs with which you interact which makes the analysis of the outgoing traffic as important as that of the incoming. The importance of API security is spread across different departments and their functions, covering different aspects of network security such as throttling and rate limiting. It also depends on identity-based security, data protection, as well as monitoring aspects.
Different Types of API – SOAP, REST, and GraphQL
The kind of API being used in the applications will define the associated security approach. Before web APIs, SOAP APIs were more popular and its security features were available through digital signatures and data encryption. It also had the advantage of portability between different network protocols such as HTTP to JMS.
As SOAP APIs dialed down in popularity, REST APIs took over with the provision of its resources being uniquely identified by HTTP URLs. The next API style is the upcoming GraphQL, an open source standard API project that extends the control to the developer. GraphQL is expected to coexist with REST APIs since the former has the unique characteristic of identifying the data requested by the user through its own query language included inside the HTTP POST body.
4 Different Layers of API Security
Since the concept of API security can be quite extensive, it’s important to identify certain subtopics under which the required steps can be defined for the business. The first stage typically involves the discovery of security vulnerabilities and in-depth details about the development of the API. There should be proper visibility into all the APIs of the organization without being disturbed by disconnected governance.
Shadow APIs can also prove to be an obstacle, being developed as a part of an application but the API itself is a part of the implementation process of the application. Details such as these are often left out which causes the lack of proper visibility and hence, poorly informed security strategies. An API often goes through the lifecycle of evolving over a period of time, either leading to new versions or gradual depreciation. Some continue to operate for some time for temporary backward compatibility but eventually disappear with decreasing traffic.
All of this requires an extensive lookout for all the APIs under the firm and exploitation possibilities, for which you can mine the API traffic metadata. This data is available from API gateways, the network traffic, or load balancers which provides a list of available APIs.
The second stage focuses on OAuth and access control processes for restricting the API resources to authorized personnel through proper verification procedures. For this, client-side applications are required to possess tokens for the API calls they make which are then validated to gain the user information. To access such a token, client-side applications need to follow the OAuth standard. The rules under which such tokens are issued and verified include the user’s privacy preferences, resources accessed, queries made, user identity, and the scope of the token.
The third stage delves into data governance and privacy standards to deal with data leaks and inspecting the API traffic to ensure data security. Data level access control is made a priority through APIs such as GraphQL which allows you to redact the user’s private information within the API traffic in real time.
Finally, the fourth stage involves API security measures such as web application firewalls (WAF) which continuously scans website traffic for SQL injection attacks, signature-based threat detection, etc. API gateways also work towards this goal by implementing strict rules for input sanitization and rate limiting that acts as additional policy enforcement.
These tips are a general guide to understanding and working with API security. However, it’s important to keep in mind that each business’ context and goals will require a specific API security strategy which should be developed with the help of cybersecurity experts.