What is API Security?

API

The dawn of technology brought with it many fascinating features and facets which we utilise daily across our devices, and software is obviously one of the cogs or keys that enables our tech to function properly.

For software applications to interact with each other as they should, there is API, or Application Programming Interface. In this article we will explore API further, why it exists, how it works, comparisons, and how to safeguard our precious interface without which our tech would be doomed.

Why API is Crucial?

As we aforesaid, tech and its systems need to talk to each other to function properly, especially nowadays with smart homes, kitchens, even fridges, or in other words the Internet of Things (IoT)

An API is crucial for this software to link and speak to one another in a way that provides what the user is requesting, Important data is being transferred from one software, system, or device to another. Users maybe sharing sensitive data, and an insecure or faulty API can result in that data being prone to leak or theft, an easy target for hackers.

Thus, a good API, one which is checked often, and updated regularly, is key to obtain a peace of mind that our software is functioning smoothly thanks to this interface, thus minimising risks.

API vs Other Alternatives

First off the bat, we must mention that the most popular type of API at present is REST (Representational State Transfer) API, as it is the most widely used architecture. This is due to its flexibility, easiness, scalability, maintainability, and compatibility with web technologies.

Other valid alternatives do exist, and we suggest that you compare reviews and/or approach experts before investing, to check what applies for your particular needs.

If we take SOAP API or Simple Object Access Protocol, it is a prime example of a secure way to build APIs, and it works by encoding data in the XML format.

On the other hand, REST API is more flexible and supports data transfer in various formats such as XML, HTML, plain text, JSON, and more.

API Security Testing – Various Methods

Hereunder we list different ways to manually test your API to check for security vulnerabilities.

Parameter Tampering – parameters sent via an API can be tampered with, as by manipulating them hackers, for example they can change purchasing prices and get products for free, or trick an API to provide sensitive user`s data. Parameter tampering enables you to test for presence of hidden fields using the browser element inspector, and check how the API reacts. 

Command Injection – operating system commands are injected in API inputs, preferably a harmless one like a reboot system. For example, if your API shows content via a URL, you can add an operating system command at the end of the URL, like restart, and see if this is executed on the server.

API Input Fuzzing – providing random data to the API until you discover a functional or security issue, is called fuzzing. API should show this by returning an error, process inputs incorrectly, or crash. For example, if your API accepts numerical inputs, you can try very large numbers, negative digits, or zero.

Unhandled HTTP Methods – HTTP methods are used to store, retrieve, or delete data. If the server does not support HTTP method, you will get an error or a security vulnerability. This applies for web applications that communicate via APIs. It can be checked if HTTP methods are supported on the server side, by making a HEAD request to an API endpoint which requires an authentication. Try all HTTP procedures namely POST, GET, PUT, PATCH, DELETE, etc.

API Testing Tools

The following are some of the top tools you can utilise to assist you in designing security-related test cases, run them against API endpoints, and remediate issues you discover.

  • Postman (API Development Platform)
  • Swagger (Open-Source Toolkit)
  • JMeter (Load Testing Tool)
  • Soap UI (API Functional Testing Tool)
  • Karate (Java API Testing Tool)
  • Fiddler (Monitors & Replays HTTP Requests)

We did not go in detail on the above, but we highly suggest you search and delve deeper to obtain the needed knowhow.

API Security Best Practices!

Take note of these top 5 recommended best practices:

  1. Encryption – this will convert your sensitive data into codes, making it much more difficult to end up in the wrong hands
  2. Authentication – like programming system to ask for user identification and password. This way who wants to access must be identified
  3. OAuth & OpenID Connect – delegate responsibilities to third party Identity Providers (IdP)
  4. Call Security Experts – seek help or assistance to scan your APIs, preventing malicious codes or data affecting your systems
  5. Monitoring – via audit, logs and versions, thanks to which you will remain constantly or regularly vigilant like an overprotective parent, wink

Again, other options do exist so we encourage you to explore, compare, and do your homework well.

API Vulnerabilities

It is imperative that you first and foremost comprehend the risks within your API system. Look for specific vulnerabilities to identify weak points, for example check for signature-based attacks like SQL (Structured Query Language) injections, use tighter rules for JavaScript, and rate limits to provide protection for API backends.

Wrapping Up

Nowadays, in a fast digital world we are very much reliant on technology, so interfaces just like API are further more appreciated. However, as we saw from this article, there is no such thing as perfection, no tech is flawless, especially if it still requires human intervention. There could be errors, or intended/malicious sabotages to the system holding a specified target like ransomware to name but one.

Creators of API and similar interfaces are to be lauded for their efforts and genius, inventing methods to enhance our tech, enabling software to interact with each other correctly and swiftly, and ultimately paving the way for progress. However, we must be cautious and vigilant as hackers will always try to break in these interfaces for their evil intentions.