API Security Primer and Best Practices for 2023
An API enables disparate software programs to communicate by allowing external clients to request services from an application. Modern web applications use APIs to share functionality and exchange data. However, by allowing this communication with external components, APIs introduce risks. API security encompasses practices, processes, and tools that help protect APIs against cyber threats. It is a core part of modern information security.
Why is API Security Important?
APIs allow you to connect critical services and transfer sensitive data. A compromised, exposed, or broken API could expose sensitive information, including personal, financial, or medical data. This failure to protect the confidentiality of your data could impact your business. Security is thus a core consideration for designing and developing a RESTful (or other) API.
Attackers can abuse an API in many ways that don’t require breaching the backend system. Various attacks can affect APIs that are not sufficiently secured, including DDoS attacks that make API endpoints unavailable or impact performance. Attackers can collect and steal data from APIs that serve data, while online shopping APIs can be the target of inventory denial attacks.
The wide range of potential attacks on an API is a major challenge for securing APIs. The proliferation of serverless and microservices architectures has made API security increasingly important for modern businesses.
What is API Security Testing?
Data is probably your organization’s most valuable asset, so it is essential to identify and eliminate threats to your data to protect that business value. An API is often the easiest component of an application for an attacker to hack, providing a path to access data.
If an API contains an error or vulnerability, it will affect all the applications relying on the API. Simply put, one API error can result in massive problems across an organization and even impact third parties using the API.
Shifting the security testing process left is critical for ensuring APIs remain secure. Developers can ensure the protection of web services using security tests that expose weaknesses to malicious attacks and prevent the exposure of sensitive data. Security testing includes various security scanning techniques to detect specific vulnerabilities. A test suite containing multiple security scans helps guarantee the service remains protected against attack.
API testing tools are software that determines whether an API fulfills the expectations for an application’s performance, functionality, dependability, and security.
6 API Security Best Practices
1. Know About the Latest Security Risks
Knowledge is key to protecting APIs. The more you know about the latest attack vectors, techniques and tools cybercriminals use to breach systems, the better you can protect your APIs.
You can gather this information from various sources, such as security news portals. You should also follow trusted sources like the OWASP top 10 API vulnerability list. You can use the information you gather to configure your APIs so that they can thwart the latest attacks.
2. Use Strong Authentication and Authorization
Publicly available APIs typically have no or very insecure authentication and authorization. However, as APIs often serve as the entrance to a database, it is critical to control the authentication and authorization mechanisms. You can use various mechanisms, such as OAuth, a token-based framework that can authorize the information shared with third parties without disclosing user credentials.
3. Use Endpoint Protection Solutions
Endpoint protection tools can help you secure endpoints such as desktops, mobile devices and laptops. You can use them to protect APIs and any servers hosting APIs endpoints. Endpoint protection solutions can help defend against threats like known malware, zero-day malware and ransomware, and prevent actors from exploiting endpoints to perform malicious actions. Endpoint security is available on-premises and in the cloud.
4. Apply Rate Limits
Popular APIs are often targeted by threat actors, typically for distributed denial-of-service (DDoS) attacks. A DDoS occurs when an actor continuously calls for service until the server crashes. You can minimize the chance of these attacks on a popular API and reduce the scope of an attack by setting rate limits. The rate limit restricts the number of times an API can be called. A rate limit can also throttle an unauthorized connection.
5. Use Quotas and Throttling
Placing quotas on the number of times the API can be called can help protect against DDoS attacks. You should also track its usage over time and analyze the behavior. Typically, if you see an increase in calls on the API, it indicates it is being abused. However, it could also result from a programming mistake; for example, calling the API in an endless loop. You can mitigate this issue by making rules for throttling that protect the APIs from spikes and DDoS attacks.
6. Validate Parameters
You can ensure incoming data does not cause harm to the API by validating the parameters. To validate parameters, you must create a strict schema describing permissible inputs to the system and passing the incoming parameters through them. Validating the parameters helps you control malicious attempts to call the API and allow only those following the verified schema.
Conclusion
In this article, I explained the basics of API security and provided six best practices you can use to improve security for your APIs:
- Know the latest security risks—Leverage security research from organizations like OWASP to understand the most important threats facing APIs.
- Use strong authentication and authorization—Ensure APIs have strong access controls and authorize accounts via the least privilege principle.
- Using endpoint protection solutions—Servers running API endpoints should be equipped with endpoint protection to prevent compromise.
- Apply rate limits—Ensure that any user or entity accessing the API can only retrieve a reasonable amount of data.
- Use quotas and throttling—Assign specific quotas to different categories of users depending on their needs or payment plans.
- Validate parameters—Always sanitize user-provided parameters before processing them, to avoid exposing the API to injection attacks.
I hope this will be useful as you improve the security posture of your valuable APIs.
