Potential Broken Object Property Level Authorization (BOPLA)

Remediation

To mitigate Broken Object Property Level Authorization (BOPLA) in an OpenAPI specification, consider these steps:

1. Fine-grained Access Control: Implement specific access controls for object properties. Define security schemes in the OpenAPI specification that restrict access based on user roles or attributes, ensuring users can only interact with properties they’re authorized to.

   securitySchemes:
     OAuth2:
       type: oauth2
       flows:
         password:
           tokenUrl: https://example.com/oauth/token
           scopes:
             userPropertyAccess: Access user properties
             adminPropertyAccess: Access admin properties
   paths:
     /user/{userId}:
       get:
         security:
           - OAuth2: [userPropertyAccess]
   

2. Selective Property Exposure: Carefully choose which properties to expose via API endpoints. Avoid generic methods like to_json() that expose all properties, and instead cherry-pick properties essential for the business functionality.

3. Schema-based Response Validation: Implement response validation mechanisms to ensure only authorized properties are included in API responses. Define strict schemas for data returned by API methods to prevent unauthorized exposure.

About

BOPLA occurs when an API fails to adequately restrict access to object properties based on user roles or permissions, potentially leading to unauthorized data access or manipulation.

Risks

BOPLA risks include unauthorized data access, data integrity compromise, and data breaches. Robust access control and careful response handling are key to mitigating these vulnerabilities in multi-tenant environments.