What Is a Business Logic Layer?

Navigating the landscape of IT involves an understanding of software architecture.

The business logic layer is critical in modern applications. It's the linchpin that holds everything together, but it's also the weakest link from a cybersecurity perspective.

Understanding how the development process works is essential for everyone involved, including non-technical employees.

In this article, you'll learn what the business logic layer is, how it works, and how cybercriminals take advantage of it.

What is a Business Logic Layer & Why Does It Matter?

The business logic layer is the connector between the database and the application, defining the rules and restrictions of how the database data is used.

In the three-tier architecture, the BLL acts as the engine of the application, separating business rules from presentation and database layers (which do not interact directly).

The BLL is often powered by APIs, making them susceptible to cyber-attacks. In fact, API attacks are projected to become the main attack vector this year.

"The business logic is the prime target for attackers because business flaws - cyber threats that occur when cybercriminals exploit the legitimate functionalities and workflows of the application to reach their malicious goals - spare them the trouble of having to do the dirty work of actually hacking your application.

What a normal criminal attacker could be going after would be data, right? So, normally, you'd have to get past the firewall and have exploits at your hands in order to gain access to a single system. Once you have that access to that system, you could pivot to other systems on the network, hoping to find the database filled with private user data that could be valuable on the dark web.

But instead of doing that, you could learn how to use the API. And if the API is not protected, you don't need to do any of that fancy hacking. Instead, you can use the API as it was designed and make queries for other users' data, and get handed everything you were looking for from the very beginning.

So without proper testing, you're leaving APIs exposed and just ripe for the picking.

- Corey Ball, Cybersecurity Consulting Manager & Author of "Hacking APIs"

How Attackers Can Attack Your Business Logic Layer

Whenever the phrase "data breach" appears in the news, it's likely to be another instance of cybercriminals abusing the business logic layer.

Venmo, USPS, Peloton, Instagram - just a few of the companies that have suffered devastating API attacks through business logic flaws.

Let's explore some of the most common ways attackers can take advantage of your BLL.

• Tampering with Data: Attackers manipulate data inputs to inject malicious code or run unauthorized commands.
• Denial of Service: Attackers disrupt business operations by flooding the BLL with more requests than it can handle.
• Spoofing: An attacker fabricates data and bypasses defenses to gain access to the system's data or functionality by posing as a known, trusted source.
• Elevation of Privileges: Attackers exploit the BLL loopholes to gain more privileges than they're entitled to or even take over the entire system through its API.

How to Protect Your Business Logic Layer for API Security

Here are some steps you can take to protect this layer from such attacks and others like them:

1. Restrict Access to the API: Only provide access to the API to authorized users. A user can be authenticated and authorized based on their role within the organization.
2. Enforce Strong Authentication and authorization mechanisms: Use robust authentication methods, such as oAuth and OpenID, to ensure that attackers can't gain access to the API.
3. Use Encryption: Protect the data being passed between the client and the server with encryption methods that prevent attackers from being able to read sensitive information.
4. Implement Rate Limiting: Use throttling to prevent attackers from flooding the system with requests, preventing DDoS and DoS attacks.
5. Log Access Attempts: Log all auditable events so that you can monitor them for suspicious activity or unauthorized requests.
6. Adopt AI-based API Security Testing: Implementing AI testing platforms ensures comprehensive and continuous testing of your APIs that manual tests can’t provide.

While many API testing tools include security as part of their package, this is not enough to prevent attacks on your business layer since issues with the business logic arise from issues with the design of your legitimate workflows.

APIsec is the only fully automated API security testing tool that can write and execute tests capable of identifying business logic flaws. The platform pressure-tests the entire API to ensure that no endpoints are left vulnerable, unlike traditional security solutions, which just look for common security issues.

You can do what you do best while APIsec automates your API security testing to ensure complete coverage at all times. Find out how APIsec can redefine how you approach API security by scheduling a free consultation.