A METHODOLOGY FOR SECURITY TESTING OF DJANGO WEB APPLICATIONS WITH AN EMPHASIS ON BUSINESS LOGIC VULNERABILITIES

Abstract

This paper presents a hands-on methodology for security testing of Django web applications with a dedicated focus on business-logic vulnerabilities–defects rooted not in low-level implementation flaws but in violated domain invariants and misdesigned workflows. We formalize domain invariants and demonstrate how to convert them into executable test oracles. The proposed process spans from threat modeling and abuse-case elicitation tailored to a given Django project to state- and property-based test design, including metamorphic testing. We explain how to instrument Django (middleware, signals, transactions, permissions, URLConf) to log, enforce, and verify invariants, and how to combine unit, integration, and API tests with dynamic and interactive techniques (DAST/IAST). We introduce business-logic coverage metrics (role-endpoint matrices, invariant coverage, and critical-scenario coverage) and provide CI/CD automation patterns. An e-commerce checkout case illustrates discount manipulation, object-level authorization, inventory race conditions, and multi-step validation bypass. Throughout, we mark concrete insertion points for figures, tables, and code listings, enabling seamless adoption by engineering teams.