Aug 16 2022

API Security: A Complete Guide

Category: API securityDISC @ 7:58 am

Our society has become increasingly dependent on technology in the past few decades, and the global pandemic accelerated this trend.

What is API Security?

APIs are prevalent in SaaS models and modern applications across the board. API security refers to best practices applied to aspects of these APIs to ensure they’re protected from cybercriminals.

Web API security includes access control and privacy, as well as the detection of attacks via reverse engineering and exploitation of vulnerabilities. Since APIs enable the easy development of client-side applications, security measures are applied to applications aimed at employees, consumers, partners and others via mobile or web apps.

Why API Security Should Be a Top Priority

Attacking APIs requires first learning about a company’s APIs. To do so, bad actors perform extensive, drawn-out reconnaissance. That activity flies under the radar of existing technology such as API gateways and web application firewalls (WAFs). APIs make a very lucrative target for bad actors since they are a pipeline to valuable data and they’re poorly defended. Since data is the lifeblood of an organization, protecting it – and end-users – is paramount to avoiding breaches and the financial and reputational harm that comes with them.

In 2017, Gartner predicted API attacks would be the greatest threat to organizations in 2022. The year has arrived, and this foresight has proved accurate. Cyberattacks on APIs have exposed vulnerabilities and cost businesses a lot of time, money and heartache to recover from these breaches.

Major organizations like Peloton and LinkedIn have recently fallen victim to API-driven attacks, proving that even enterprise-class businesses (with enterprise-class budgets) are no match for cybercriminals. API attacks grew an astounding 681% in 2021, showing that businesses cannot afford to be complacent about this threat.

API Security Checklist for Development and Implementation

As with any security objective, it’s crucial to implement best practices and ensure you close all gaps in your API security strategy. While it can be overwhelming, an organized approach will help break your plan into manageable pieces. Start with scope and prioritization:

  • Perform penetration tests for your APIs, and know that to get a clear picture of the security status, you’ll need runtime protection
  • Assess the entirety of your environments, including your digital supply chain and APIs that fall outside of your API management suite
  • If you need to start small, prioritize runtime protection to protect from attackers while your application and API teams delve further into the comprehensive security strategy

Design and Development

Building a robust API security strategy is crucial, but that doesn’t mean you need to start from scratch. Great supportive resources, including the OWASP Application Security Verification Standard (ASVS), are available to help you design your approach.

Ensure you draft your organization’s build and integration security requirements, include business logic when performing design reviews and implement practices for coding and configuration relevant to your security stack.


Ensure that you keep comprehensive documentation for application and integration teams. Documentation should cover security testing, design reviews, operations and protection. By documenting the stages of your process, you will ensure continuity in your testing and protection approaches.

Discovery and Cataloging

Ideally, your documentation process will be thorough and consistent. In reality, however, sometimes things are missed. Therefore, organizations must implement automated discovery of API endpoints, data types and parameters. You will benefit from this approach to create an API inventory to serve IT needs throughout your organization.

Ensure you use automation to detect and track APIs across all environments, not limiting the focus to production. Be sure to include third-party APIs and dependencies. Tag and label your microservices and APIs—this is a DevOps best practice.

Security Testing

Traditional security testing tools will help verify elements of your APIs, including vulnerabilities and misconfigurations. Bear in mind that while helpful, these tools do have their limitations. They cannot fully parse business logic, leaving organizations vulnerable to API abuse. Use tools to supplement your security strategy, and do not rely on them as a be-all-end-all view of the state of your APIs.

Security at the Front-End

For a multi-layered approach, ensure you implement a front-end security strategy for your API clients that depend on back-end APIs. Client-side behavior analytics can embellish privacy concerns while protecting the front end. It is recommended to draft security requirements for your front-end code and to store minimal data client-side to reduce the risk of reverse engineering attacks. Ensure you have secured your back-end APIs as well, as this is not an either/or approach.

Network and Data Security

In a zero-trust architecture framework, network access is dynamically restricted. It is still possible for API attacks to occur due to the connectivity required for API functionality, meaning trusted channels can still create security threats. Ensure your data is encrypted during API transport, and use API allow and deny lists if your user list is short.

Many organizations are unclear on which APIs transmit sensitive data, exposing them to the risk of regulatory penalties and large-scale data security breaches. For data security, transport encryption is suitable in most use cases.

Authentication, Authorization, and Runtime Protection

Accounting for authentication and authorization for both users and machines is crucial to a comprehensive API security approach. Avoid using API keys as a primary means of authentication, and continuously authorize and authenticate users for a higher level of security. Modern authentication tools such as 0Auth2 will increase security fortitude.

Organizations should deploy runtime protection. Make sure your runtime protection can identify configuration issues in API infrastructure. It should also detect behavior anomalies such as credential stuffing, brute forcing, or scraping attempts. DoS and DDoS attacks are on the rise, and you should be sure that mitigation plays a role in your API security strategy.

API Security is Fundamental in Today’s World

The use of APIs is a fundamental element of life in the modern era. As such, organizations have a responsibility to ensure end users, networks and data are kept safe from intruders who may expose API vulnerabilities. By following these key aspects of API security, you will be able to successfully mitigate risk.

API Security in Action

A web API is an efficient way to communicate with an application or service. However, this convenience opens your systems to new security risks. API Security in Action gives you the skills to build strong, safe APIs you can confidently expose to the world. 

API Security in Action

Tags: API Security

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