NodeJS Broken Object Level Authorization Guide: Examples and Prevention

Broken object-level authorization (BOLA) is highlighted as a critical threat to API security, deemed the top concern by OWASP in 2023, due to its potential to allow unauthorized access to sensitive data when API endpoints fail to properly validate user permissions. This article, aimed at NodeJS and JavaScript developers, explores how BOLA attacks exploit poorly implemented authorization mechanisms, using examples of vulnerabilities where user or object IDs are manipulated. It details mitigation strategies, such as implementing robust session-based authorization systems in NodeJS, to prevent these attacks. The emphasis is on ensuring that user IDs in session objects match user-provided values and confirming that users have access to requested objects. The author, Juan Reyes, underscores the importance of robust security practices and recommends using dynamic application security testing (DAST) tools, like those from StackHawk, to detect and address such vulnerabilities in real-time.