Application programming interfaces (APIs) facilitate connections between applications and external users to transfer data that can include anything from users’ credentials to personal information. With API usage growing exponentially, API vulnerabilities have become a primary target for cyber threats. An insecure API makes our data vulnerable and puts the sensitive data of other connected applications at risk. So, it is important to implement security measures to safeguard the data.
To protect our APIs, we first need to understand the methods through which malicious users may attack. A few of the primary methods are as follows:
Stolen authentication: The simplest way to access an API is to steal a user’s authentication token to access resources and sensitive data, such as credentials.
Man-in-the-middle attack: A man-in-the-middle attack intercepts a user’s or API’s request or response to modify it or steal data, which may include credentials or other sensitive information. This is possible due to excessive data exposure during communication.
Insufficient authentication: When users aren’t adequately authenticated, the API may receive bogus or potentially malicious calls that may hinder its functionality and lead to issues in access control.
Code injections: APIs with insufficient authentication are also vulnerable to code injections, carried out through cross-site scripting (XSS) or SQL injections to do different malicious activities.
Distributed denial of service: In a denial of service attack, a service or system is overloaded with requests to disrupt the regular functionality. These attacks are simultaneously made from multiple sources distributed across the regions.
By analyzing the types of attacks, we need application security (both client and server-side) and data security (both at rest and in transit) to secure our APIs. Therefore, API security becomes a combination of all these security methods:
To guard our APIs against these attacks, we must implement security mechanisms that best protect APIs and sensitive data associated with the users.
API security can be achieved by adhering to best practices that mitigate vulnerabilities and prevent potential attacks. We describe practices suited for all three paradigms, i.e., application, network, and data. We apply the following core mechanisms, among others:
Let’s discuss a few of the API security mechanisms.
We need to implement robust mechanisms for
We must utilize strong authentication protocols like OAuth or
Once a user is authenticated, we must ensure that the user or service has defined permissions and can access resources or perform intended operations. This can be achieved using JSON web tokens (JWTs) and ensures access to data and functionality the user needs.
For example, if we select sign-up on Educative using Google, the Educative authenticates the identity from Google, which further requests users to authorize the Educative to access a piece of certain information, as illustrated below:
We must verify the data entering the API on both the client and server sides. It’s an essential aspect that prevents tampering, code injection attacks, and information disclosure and should be implemented in every API.
We should consider encrypting data both in transit and at rest in databases. While data is in transit, we must secure the communication by encrypting data using end-to-end encryption. We can encrypt all the data using transport layer security (TLS) encryption protocols like HTTPS. Similarly, we should also store sensitive data in encrypted format using highly secure encryption algorithms like advanced encryption standards (AES). In this way, data remains secure even if any unauthorized user gets access to it.
We can use an API gateway as a central single entry point for managing and securing all incoming and outgoing API traffic. It can function as a protective barrier as it can be used to authenticate, authorize, rate limit, and monitor the traffic. Moreover, we can implement a rate limiter to restrict the number of API calls for a user or service. This is crucial to mitigate denial of service attacks aimed at overloading a service by multiple requests. We can use throttling to dynamically adjust the rate limit for legitimate users based on resource availability.
API monitoring is the process of analyzing overall API performance to identify problems that can impact developers and users of the API. It helps maintain logs of all requests and responses, allowing us to track user activity, identify suspicious behavior, and investigate potential security risks beforehand.
By implementing these security practices as norms, we can significantly strengthen our API security. Although it is an ongoing process that requires continuous improvement, adaptation, and adherence to new norms, the basic principles remain the same. We should prioritize security while designing the APIs to ensure they remain reliable and secure for users.
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