Business Logic Testing

Business logic testing is a more comprehensive approach to API security testing that examines how endpoints work together rather than treating them in isolation. Instead of only validating inputs and outputs for individual endpoints, business logic testing considers the actual functionality and workflows that your APIs implement.

Consider a simple e-commerce application with an /addItem endpoint and a /checkout endpoint. Traditional testing might call these independently, validating inputs and outputs separately. Business logic testing recognizes these endpoints as part of a connected workflow—items must be added before checkout occurs, cart totals should match item prices, and payment processing follows specific business rules. This contextual understanding enables detection of vulnerabilities that isolated endpoint testing would miss.

Coverage of OWASP API Vulnerabilities

Business logic testing addresses several critical API security risks identified by OWASP:

• BOLA (Broken Object Level Authorization) - Testing whether users can access objects they’re not authorized to view
• BOPLA (Broken Object Property Level Authorization) - Validating that users can only modify properties they have access to
• BFLA (Broken Function Level Authorization) - Verifying that privileged functions remain protected from unauthorized access
• Additional business logic vulnerabilities specific to your application’s workflows

Configuration Approach

StackHawk provides several plugins that vary in configuration complexity and testing depth. There is a direct relationship between how much the scanner knows about your system and the number of vulnerabilities it can identify. This creates a trade-off between ease of configuration and scan comprehensiveness.

The plugins are organized from simple (minimal configuration required) to advanced (significant configuration effort, maximum testing depth), allowing you to select the appropriate level based on your security requirements and available resources.

Least Configuration

StackHawk provides several out-of-the-box plugins designed for business logic testing with minimal configuration overhead. These plugins automatically detect common authorization and access control vulnerabilities without requiring deep knowledge of your application’s internal business rules. While these plugins are not enabled by default, they can be quickly activated through policy management, allowing you to begin testing for business logic vulnerabilities immediately.

The following plugins are available for easy enablement:

• 422002 - Multi user tenancy check - Validates tenant isolation in multi-tenant applications
• 40054 - API Broken Object Property Level Authorization - Detects improper restrictions on object property access
• 421004 - Possible Broken Object Property Level Authorization (BOPLA) - Identifies potential property-level authorization issues
• 40051 - API Broken Function Level Authorization - Tests for inadequate function-level access controls
• 422003 - Possible Broken Function Level Authorization - Flags likely function-level authorization weaknesses

Medium Configuration

Coming Soon

StackHawk is actively developing mid-level business logic testing capabilities that will bridge the gap between out-of-the-box plugins and fully custom scripting. These upcoming features will provide configurable test patterns that understand common application workflows and business logic scenarios, requiring moderate setup effort while delivering significantly enhanced vulnerability detection capabilities.

Most Configuration

For organizations requiring the deepest level of business logic testing, StackHawk’s custom scripting functionality provides complete flexibility to model your application’s specific workflows and business rules. Using the full power of the HawkScan Testing Engine (HSTE), you can create tailored test scripts that precisely match your system’s unique logic patterns, user roles, and authorization models.

Custom scripts enable you to:

• Define multi-step workflows that mirror real user interactions
• Test complex authorization scenarios specific to your business domain
• Validate state changes and data consistency across related endpoints
• Model role-based access patterns unique to your application

This approach requires investment in understanding both your application architecture and the HSTE scripting capabilities, but delivers the most comprehensive business logic vulnerability detection possible. For detailed guidance on implementing custom test scripts, check out our documentation.