Modern REST API Broken Object Level Authorization (BOLA/IDOR) Analysis
ENVIRONMENT: Dockerized Microservice Lab (PHP 8.4 Phalcon + PostgreSQL)
VISIBILITY: Public
TOOLS:
Postman
OWASP ZAP
Burp Suite Pro
K6
01 // Objective
Identify authorization flaws and IDOR vulnerabilities in financial API endpoints and implement zero-trust attribute-based access control (ABAC).
02 // Methodology & Execution Steps
1. Authenticated as User A and swapped target object IDs to access User B financial transaction history.
2. Analyzed predictability vectors between sequential integer IDs and cryptographically random UUID v7.
3. Implemented user-scoped database queries and validated 403 Forbidden enforcement.
03 // Findings & Attack Vector Verification
Authenticating requests is meaningless without granular object ownership validation. Obscuring identifiers via UUIDs slows down enumeration but leaves the authorization hole wide open.
04 // Remediation & Layered Defense
Enforce user-scoped repository queries (`WHERE id = :id AND user_id = :active_user_id`) and integrate centralized authorization policy middleware.
05 // Lessons Learned & Engineering Takeaways
Access control must be enforced at the deepest data layer, not deferred to client apps or frontend gateways.