Application programming interfaces (APIs) are the essential building blocks that transform how organizations drive innovation, modernize their infrastructure, and connect with customers and partners. A study found that API growth has been exponential in recent times and has increased by 167% in the past year.

Because of their rapid proliferation and central role, APIs have become a prime target for hackers. This has led to a rise in API-related breaches, making API security a critical business need. Such data breaches have wide-ranging implications for businesses. These include exposing customers’ personal data, loss of trust, disruption of business services, compliance violation, and loss of productivity.

Considering the impacts of compromised APIs, businesses must adopt a proactive approach to protect them. One method is to embrace a zero-trust architecture. A zero-trust framework is a robust security system based on the principle ”trust nothing and verify everything.” However, the question is how to implement this approach and protect APIs from abuse. This blog post delves into this issue, but before that, let’s first understand the API threat landscape.

The Growing API Threat Landscape

The API threat landscape is intensifying over time due to increasing complexities within IT environments. The State of API Security Report 2025 by Traceable AI reveals that 67% of organizations consider generative AI applications a severe threat to API security. In addition, 60% believe that API integration required for these apps increases the attack surface and expresses deep concerns about data exposures and unauthorized access.

Many cybersecurity issues in recent years have emerged from API misconfigurations. These include improper authentication, authorization, rate limiting, logging and monitoring, and lack of input validation. Wallarm’s researchers discovered a 21% increase in API vulnerabilities from the second quarter of 2024. These vulnerabilities had an average Common Vulnerability Scoring System (CVSS) score of 7 (out of 10), with many scoring 7.5, highlighting high severity and how easily hackers can exploit flaws within the APIs.

APIs have become a top attack vector for threat actors because of a lack of visibility, stemming from API sprawl. Imperva’s research showed that API traffic accounted for 71% of all web traffic in 2023 and that, on average, enterprises make 1.5 billion API calls annually.

Organizations are often unaware of the total number of APIs they have and where they reside. As these APIs are not tracked or monitored, this lack of visibility can expose sensitive data, including financial records, business databases, or customers’ personally identifiable information (PII). What’s more concerning is that such incidents occur silently without anyone noticing until the damage is done.

To overcome these challenges, organizations must adopt a proactive approach to API security and implement controls where necessary.

Understanding the Importance of Zero-Trust APIs

The traditional network perimeter approaches to security, like firewalls, no-logs virtual private networks (VPNs), or other access control mechanisms are no longer effective in today’s API economy mainly because of the unique nature of the APIs and how they interact with the systems. This results in embracing a zero-trust architecture that offers more granular security by assuming everyone is untrustworthy inside and outside the network perimeter and emphasizes continuous authentication and authorization of the entities interacting with the APIs.

Extending zero-trust principles to APIs is an effective strategy for protecting APIs as it is highly scalable and can be extended across any network. A report by Microsoft also revealed that 96% of security decision-makers agree that a zero-trust approach plays a vital role in organizational success.

A zero-trust model assumes that each API is a potential security risk. Therefore, every API request needs to be authenticated, authorized, and validated before granting access. It employs least privilege access policies, a key approach to zero-trust that controls who can access the APIs and what actions they can take. This ensures only devices and users have access to the specific API endpoints they require, reducing the risk of unauthorized access and over-exposure.

Microsegmentation is another vital element of the zero-trust model that breaks down the network into smaller and controlled sections. Doing so limits the impact of cyberattacks, meaning if attackers access one part of the network, they can’t move laterally to another part. This is important to APIs because attackers often target them because of their open nature.

By segmenting the most crucial APIs first, DevOps and IT security teams can apply access control policies on each segment. They can also have better control and visibility into APIs and the level of access users have. In addition, with smaller and fewer pathways, it becomes challenging for attackers to penetrate the network, reducing the attack surface and the likelihood of API breaches. This is extremely useful in the healthcare industry, where APIs handle sensitive healthcare data. In fact, 78% of healthcare organizations experienced an API-related incident in 2023.

Besides this, with the proper monitoring in place, a zero-trust security approach enables continuous analysis of the behaviors of devices and users interacting with the APIs. Any deviation from expected behavior can alert the security teams so they can take timely action and prevent the exploitation of vulnerabilities and the risk of API abuse.

Overall, this layered security approach provides a proactive and scalable approach to safeguard APIs from data leaks and even helps organizations meet various compliance regulations.

Advanced Solutions for Deploying Zero Trust for API Security

Implementing a zero-trust approach to protect APIs requires using specific tools and technologies. Let’s consider the three best tools for implementing zero trust.

API Gateways

API gateways are essential for your API management system and the security of your APIs. They act as an intermediary pathway that monitors, authenticates, and authorizes the entire API traffic. An API gateway validates every API request by enforcing access control policies, ensuring only authorized users and devices can access the APIs.

Besides this, API gateways can seamlessly integrate with identity and access management (IAM) solutions and enforce granular access controls that allow verified users to interact with the APIs. Like the zero-trust architecture, it also offers real-time monitoring and logging capabilities to determine API behavior and pattern and helps mitigate the risks of cyberattacks.

Web Application and API Protection (WAAP)

Web application and API protection (WAAP) is a set of security technologies designed to protect both APIs and web applications from cyberattacks. Various WAAP providers like Akamai and Cloudflare offer API management capabilities, including real-time monitoring and threat detection, which enable your organizations to uncover and protect against API-based attacks.

These services also offer authentication and authorization mechanisms like API tokens and OAuth to validate API requests and responses and prevent common API vulnerabilities. In addition, they leverage an advanced rate-limiting feature to control the rate of incoming API requests based on various factors like the number of requests per minute or hour. This way, it aligns with the zero-trust model, effectively manages API traffic, and protects it from abuse.

Identity and Access Management Solutions

As you all know, identity and access management refers to the policies, processes, and technologies that allow organizations to control and manage user identities, access, and privileges to applications and systems. These solutions mainly include authentication, authorization, user provisioning, and auditing capabilities, some of which are essential components of the zero-trust security approach.

IAM verifies each API request using multi-factor authentication (MFA) and token-based authentication mechanisms, reducing the risk of over-permissioned access. Besides this, it monitors and logs all API access points, which provides visibility into which APIs exist and how they’re accessed and reduces the risk associated with API sprawl.

Final Thoughts

API security is no longer a technical challenge and has become a business necessity. By prioritizing security and embracing a zero-trust approach that explicitly verifies every user and device accessing the APIs, you can safeguard assets, mitigate the likelihood of data breaches, and maintain a competitive edge in the market.