Application programming interfaces (APIs) have played a crucial role in the digital revolution seen across the Internet of Things (IoT), mobile and web applications, as well as cloud computing. In many ways, APIs have become an integral part of our daily lives, with the average person unknowingly interacting with them several times a day, especially on mobile devices.
In essence, APIs serve as the glue that transfers information between systems, both within and beyond an organisation. Unfortunately, many APIs are deployed without undergoing through security testing, or in the worst case, without testing for security at all. Regardless of its type, a poorly secured API can create vulnerabilities that affect everything it is connected to. Therefore, it is crucial to prioritise the security of APIs just as much as the applications that rely on them.
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What Is an Application Programming Interface?
Simply put, an application programming interface acts as a bridge between different software programs. By following a set of established rules, these systems would be able to communicate with each other via APIs. With that, APIs can be seen as the messenger that facilitates data transfer between applications. Meanwhile, there are two main types of APIs, namely the Representational State Transfer (REST) and Simple Object Access Protocol (SOAP).
APIs are widely used in many popular web and mobile applications today. They enable companies to collaborate with external developers, suppliers, and partners by allowing information to flow between systems. What’s more, by integrating multiple software components, APIs allow for seamless data transfer within a system. The problem, however, is that APIs also present a potential security risk as they can serve as an entry point for malicious hackers looking to access sensitive information processed by these applications.
What Is an API Penetration Test?
Fundamentally, API penetration testing is an ethical hacking method used to evaluate the security of an API’s design. The process involves attempting to exploit potential vulnerabilities and reporting the findings as part of improving the API’s security and thereby preventing unauthorised access or data breaches in the future.
API penetration testing involves simulating a third-party attacker’s actions to uncover any weaknesses that could be exploited. This includes testing for security risks such as structured query language (SQL) injection, cross-site scripting (XSS) attacks, as well as other forms of API-level vulnerabilities. Not to mention, it is crucial to understand that API penetration testing is different from testing the overall security of an application, given that this test specifically concentrates on the API itself.
Why is API Penetration Testing So Important?
Conducting API penetration testing is crucial for safeguarding the security of an application. This type of testing enables the detection and resolution of potential security weaknesses before they can be taken advantage of by external malicious actors. Besides that, such practices also verify that the API is functioning properly and that there are no unforeseen security risks.
By performing regular penetration tests, organisations can be proactive in minimising the likelihood of security breaches and subsequently safeguarding their data as well as systems. Additionally, API penetration testing can assist organisations in meeting compliance and privacy regulations.
What Are the Common Types of Vulnerabilities Present in APIs?
Essentially, there are a number of types of vulnerabilities that may be present in APIs, but three are particularly prevalent:
Inadequate Authentication and Authorisation
In short, this security weakness enables one to have unauthorised access to an API, making it possible for malicious actors to access sensitive data or perform actions that ought to be restricted.
Unsatisfactory Rate Limiting
This security vulnerability permits too many requests to be made to an API within a specific time frame. As a result, this weakness can be targeted by attackers, which may overload the API server or carry out denial-of-service attacks.
Insecure Communication Channel
This security vulnerability exposes the communication channel between the API client and server to interception. Consequently, this can be leveraged by third-party hackers to tap in on conversations or access top-secret information.
How Does the API Penetration Testing Methodology Look Like?
All in all, API security testing is a procedure to assess the robustness of an API in order to verify that it is operating correctly and not prone to external threats. On that note, the following are the key steps that take place during an API security test:
API discovery
This step involves locating the API to be tested and comprehending its operations.
Definition of the attack surface
Put simply, the attack surface refers to all possible ways in which the API can be targeted.
Identification of security measures
Security measures are the systems in place to secure the API from breaches.
Assessment of security measures
This step entails evaluating the security measures to confirm their efficacy in protecting the API.
Conducting the actual API penetration test
This step involves attempting to penetrate the API to check if any known vulnerabilities can be exploited.
Finally, the outcome of the penetration test is communicated to the organisation, and further testing may be carried out if required.
What Are Some Examples of Best Practices to Circumvent API Vulnerabilities?
Organisations can suffer severe consequences from API breaches, including loss of data, harm to reputation, and potential legal issues. It is crucial to implement effective security measures to prevent such incidents. Having mentioned a few examples of such measures would include the following:
Real-Time Monitoring
Establishing a real-time monitoring system is key to safeguarding your API from breaches. By monitoring all potential entry points, breaches can be detected and prevented prior to them causing any harm.
Regular API Scans
Regular scans of APIs play a significant role in ensuring comprehensive security. These scans help detect vulnerabilities that may go unnoticed. Other than that, the API scans can be performed manually or with automated tools, which automated tools are typically more capable of providing comprehensive coverage and may be run more regularly.
Careful Handling of User Data
In short, developers must be cautious when working with user-generated data. In particular, just because a user inputs information into a form or text box doesn’t guarantee its accuracy or safety. Hence, always assume that the user data is malicious until verified, and continue to exercise caution even after the verification process has been completed.
The open-appsec programme applies all of the above security measures. It is a novel open-source initiative that builds on machine learning to offer enterprise web applications as well as API security. As a result, the open-appsec programme would be able to provide the API vulnerability protection, visibility, and manageability that a modern organisation will need. Moreover, the open-appsec programme may be deployed as an add-on to API Gateways, Envoy, Kubernetes Ingress, and NGINX.
Concluding Thoughts
All in all, API penetration tests ought to be a core component of an organisation’s API security programme. With the emerging cyberattack landscape, this, in turn, requires the rigorous evaluation of API endpoints for security vulnerabilities that have a large impact on the company’s digital ecosystem, data, and users.
