Granular authorization system for modern applications.
Auth0 Fine-Grained Authorization enables precise access control by defining permissions and roles at a detailed level, allowing applications to enforce who can perform specific actions on specific resources.
This advisory offer was created to support organizations with architecting and building modern authorization systems leveraging Auth0 Fine-Grained Authorization.
OWASP API Security Project is an initiative by the Open Web Application Security Project (OWASP) focused on addressing security issues related to Application Programming Interfaces (APIs). The most popular vulnerabilities related to authorization are:
Security flaw where an application doesn’t properly check whether a user has permission to access a specific piece of data.
Security flaw where an application doesn’t properly check whether a user has permission to perform certain actions or access specific functions. This allows users to perform actions they shouldn’t be able to, like accessing admin features or modifying other users’ data.
Security issue where an application fails to properly check if a user has permission to access or modify specific properties or fields of an object. This means that even if a user is allowed to access an object (like a profile or document), they might be able to change details or fields they shouldn't have control over.
When building new application solution it is important to utilize modern approach to authorization. Here are some of the differences between traditional approach and modern approach.
Coarse-grained, tenant-level permissions (RBAC).
Complicated authorization code embedded in the application.
Permissions evaluated at login time and roles included in the tokens.
Fine-grained: resource-level permissions (ABAC, ReBAC).
Authorization logic extracted out of the application (centralized).
Real-time permissions evaluation before granting access to resource.
There can be multiple ways of implementing authorization. However, Tech Mind Factory prefers to use industry standards.
OpenID AuthZEN is an extension of OpenID Connect that focuses on fine-grained, real-time authorization decisions. It provides well defined Authorization API.
While OpenID Connect mainly covers authentication (proving who a user is) and some basic authorization (scopes/claims), AuthZEN goes further by enabling applications to dynamically check whether a specific action on a resource should be allowed, in a standardized way.
It is designed to support Zero Trust architectures, where every request must be explicitly authorized, not just authenticated once.
Auth0 Fine-Grained Authorization (FGA), combined with the emerging OpenID AuthZEN standard, addresses this need by enabling real-time authorization decisions. With Auth0 FGA, applications can define complex relationships between users, roles, and resources in a highly scalable graph-based model. Instead of embedding authorization rules directly into application code. This approach reduces complexity, improves maintainability, and ensures that access controls remain aligned with evolving business requirements.
By leveraging Auth0 FGA with OpenID AuthZEN, organizations can implement a robust authorization strategy that is standards-based, future-proof, and adaptable to complex use cases. This solution provides a clear path toward implementing Zero Trust principles while reducing operational overhead and accelerating the secure delivery of digital services.
This video includes the overview of some important concepts related to Auth0 FGA.