Supabase Security: The Hidden Dangers of RLS and How to Audit Your API 🛡️

Supabase has solidified itself as the developer's favorite Open Source alternative to Firebase. The promise is incredible: you build a relational PostgreSQL database and magically get an instant REST API (via PostgREST) ready to be consumed by your frontend. But exactly in this "magic" lies the danger. The convenience of having an API that directly reflects your database schema brings a massive cyber risk if you ignore (or misconfigure) the heart of Supabase security: RLS (Row Level Security) . In this article, we'll break down how data leaks happen and how you can automate the pentesting of your application before going to production. 🛑 The Problem: The Default Trap In traditional APIs (Node.js, Laravel, Spring), security lives in the backend. You write middlewares and controllers to block unauthorized access. In Supabase, the logic is inverted: access control lives inside PostgreSQL . The database acts as the bouncer, evaluating RLS rules row by row. The main issue? By default, when