API security aims to protect APIs from attacks and data breaches.
When we use software applications, such as mobile apps, we take it for granted that the information we request will be delivered quickly and clearly. Before this can happen, however, a vital process must occur: the app connects to the internet and sends data to a server, which retrieves that data, interprets it, performs the necessary actions, and sends us what we have requested – all of which happens via an Application Programming Interface (API).
This ability to serve as an intermediary between two software applications so they can exchange data seamlessly means APIs are fundamental to digital transformation in today’s app-driven business world: they enable mobile experiences, connect companies on the web, and facilitate platform business models.
More than 83% of enterprises use APIs to increase ROI on their digital assets. However, they have become victims of their success. Their ubiquity (coupled with their ability to enable access to sensitive software functions and data) has made them a primary target for cyberattacks.
Common API Security Vulnerabilities
Let’s explore five of the most common API vulnerabilities that can lead to network breaches, compromised data, and financial loss for businesses, and provide some tips to help prevent them:
Broken user authentication
This occurs when the user’s session ID or credentials have been compromised due to weak API authentication protocols, allowing attackers to take over their accounts, steal their data, or engage in fraudulent transactions.
Recent research reveals that 94% of applications were found to have some form of broken access control, with an average incidence rate of 3.81%
- Prevention tip: All authentication endpoints should be protected by strict rate limiting, lockout policies, and weak password checks.
Broken object-level authorization (BOLA)
This occurs when attackers exploit vulnerable API endpoints by manipulating object IDs in API requests. With no check in place to determine ownership of those objects, attackers can access sensitive information by simply changing the ID in a request.
Recent analysis of prevalent security challenges in live APIs identified Broken Object-Level Authorization (BOLA) and injection attacks as the leading issue (37%).
- Prevention tip: Enforce robust authorization mechanisms and redefine how you generate and manage IDs within your API ecosystem.
Injections
This occurs when attackers inject malicious code or commands into APIs through user input fields, allowing them to exploit vulnerabilities or manipulate data. This technique can be effective when APIs don’t properly validate or sanitize user input, or when they don’t properly handle external data sources or systems.
- Prevention tip: Validate, sanitize, and/or escape user inputs by performing data validation using a single, trustworthy, and actively maintained library.
Excessive data exposure
This occurs when an application, via an API response, provides too much information to the user, meaning they can’t perform a specific action. This reliance on the client side can expose unfiltered data that an attacker can intercept.
Recent analysis of prevalent security challenges in live APIs identified data exposure as one of the leading issues (34%).
- Prevention tip: Treat every response and data field as a vulnerability. Review the API responses to ensure they contain only legitimate data.
Lack of rate limiting
This occurs when an API does not limit the number of requests a user or system can make in a given timeframe. This can lead to potential Denial-of-Service (DoS) attacks, where a cybercriminal overwhelms the API with requests, causing it to become unresponsive.
- Prevention tip: Limit how often a client can call the API within a defined timeframe and notify them when the limit is exceeded.
What is API Security?
APIs play a vital role as the backend framework for software systems and services, making them a conduit for sensitive data, including access information like authentication and authorization, and attracting unwanted attention from cybercriminals.
API security protects these backend frameworks from cyberattacks that try to exploit them by gaining unauthorized network access to steal sensitive data or disrupt services.
Organizations deploy strategies and tools to restrict access to authorized users only and protect data transmitted through the API from compromise or manipulation.
Top 6 API Security Best Practices
The widespread use of these business-critical software interfaces has meant that their vulnerabilities and the nefarious techniques used to exploit them have expanded the cyber-attack surface.
To mitigate this threat and protect future revenue and growth, businesses must ensure API requests are authenticated, authorized, validated, cleansed, and resilient under load. This requires developing and implementing a robust API security strategy built on a foundation of the following best practices.
1. Authentication
The first layer of defense against unauthorized access to API resources should be a robust authentication system – using standards such as OAuth 2.0, OpenID Connect, and JSON Web Tokens – that requires users to provide specific login credentials before gaining access to data.
This process of thoroughly authenticating all related users and devices typically requires client-side applications to include a token in the API call, allowing the service to validate the client.
2. Encryption
Encrypt all network traffic – notably API requests and responses, as they likely contain sensitive data. Secure these communications between APIs and clients with an SSL connection or a TLS-based protocol like HTTPS.
For maximum security, use the latest and most secure version of HTTPS with TLS 1.3 protocol enabled for all software applications. This ensures all data sent between them is encrypted and protected from malicious third parties.
3. Access control
Introduce and test controls to manage the level of third-party access to internal data and systems through APIs. This requires a “never trust, always verify” mindset that’s underpinned by three questions: Who? What? When? Known as a zero-trust strategy, this authorization strategy controls data access, creation, update, and deletion.
To reinforce access control, keep APIs behind a firewall, web application firewall, or API gateway, and require a secure protocol to provide standard protections, such as scanning for injection-based attacks.
4. Only share the necessary information
API responses typically include an entire data record rather than just the relevant fields.
If the client application fails to filter this sensitive data before making it publicly available, it not only slows response times; it also gives attackers additional information about the API and the resources it accesses, such as keys, passwords, and other personal information needed to fulfill a request. For example, if a customer’s age is requested, don’t also provide their date of birth.
5. Record APIs in a registry
You can only secure what you know. To do this, record all APIs in a registry and define key characteristics such as name, purpose, and live date. By recording pertinent information, you will be well-placed to meet compliance and audit requirements and assist in forensic analysis during a security incident.
The registry should include all technical API requirements, such as functions, classes, and integration processes.
6. Assess risks
Conduct a comprehensive risk assessment for APIs in your existing registry that identifies all systems and data that will be impacted if an API is compromised. Use this insight to outline a treatment plan that contains the controls needed to trim risks to an acceptable level. This will empower you to implement measures that ensure compliance with security policies and protection against known vulnerabilities.
To maintain robust security, document review dates and conduct periodic assessments, particularly in response to new threats or API modifications. Review this documentation thoroughly before making subsequent code changes to ensure security and adherence to data-handling requirements.
7. Monitoring
By continually monitoring your APIs, you can see what users access and what they do with that information. Be vigilant by recording every API request and maintaining audit logs of user activity. Robust governance provides the agility needed to troubleshoot errors and maintain data security and compliance.
Create and implement a comprehensive auditing and logging policy regularly reviewed and updated to keep up with pervasive cybersecurity threats.
Conclusion
As the backbone of modern applications, APIs create opportunities for businesses to elevate services, engage customers, increase productivity, and maximize profits, but only if they’re secure. To do this, API security must be a systematic process that addresses every weak point cybercriminals might target and keeps pace with the dynamic cyber threat landscape.
Connect with our client-side security experts to learn more and how to use Jscrambler solutions to protect your client-side assets.
