Authentication vs. Authorization: Understanding the Key Differences

TL;DR

Authentication is about who you are. Authorization is about what you're allowed to do. Confusing the two leads to serious security gaps—especially in AI-generated or vibe-coded apps.

Why This Matters

If you're building an app—whether you're a seasoned CTO or vibe-coding your MVP with Cursor or Windsurf—you need to understand the difference between authentication and authorization.

Too many developers conflate them or build one and assume the other is covered. That’s how security flaws creep into your stack: exposed admin panels, broken permissions, or data leaks.

What Is Authentication?

Authentication is the process of verifying who a user is.

It answers questions like:

• Is this person who they claim to be?

• Can we verify their identity with a password, Google login, or magic link?

• Has their session expired?

In AI-built or vibe-coded apps, basic login flows are often implemented fast. But missing pieces—like password resets or multi-factor authentication—leave serious gaps.

Common Authentication Methods:

• Username & Password

• Magic Links

• OAuth (Google, GitHub)

• TOTP / Authenticator Apps

• Passkeys / WebAuthn

What Is Authorization?

Authorization defines what a user is allowed to do after they’ve been authenticated.

It answers questions like:

• Can this user edit this record?

• Is this user allowed to see this data?

• Should this API call be permitted for their role?

This is where concepts like RBAC (role-based access control) or ABAC (attribute-based access control) live.

In many vibe-coded apps, authorization is completely skipped. Once someone is logged in, they have access to everything. That’s a huge risk.

Why the Confusion?

Because they often happen back-to-back.

You log in, then you access stuff. But authentication just verifies identity. Authorization governs what comes next.

Hotel analogy:
Authentication is showing your ID at check-in.
Authorization is whether your keycard opens the penthouse.

The Security Impact

Here’s what happens when you get this wrong:

• Skip authentication → Anyone can access the app

• Skip authorization → Anyone can do anything once logged in

• Combine them naively → Privilege escalation risks

• Assume OAuth = security → Authorization is bypassed entirely

The Risk in AI-Built & Vibe-Coded Apps

With AI-generated apps, it’s easy to get a working login flow without fully thinking through security.

You might:

• Skip role checks

• Forget to restrict access

• Leave admin endpoints exposed

• Reuse boilerplate that doesn’t enforce rules

You may not notice until it’s too late—or until your first enterprise customer hands you a security questionnaire.

How Prefactor Helps

At Prefactor, we make sure authentication and authorization are secure, scalable, and separated cleanly.

What you get:

• Full authentication stack: password, Google login, magic links, TOTP, SSO

• Code-defined authorization: RBAC and ABAC via a DSL

• Observability and audit logs built in

• CI/CD-friendly workflows with version control

You don’t have to hand-roll anything. You define your logic once, and Prefactor handles the rest—securely.

Final Takeaway

Don’t treat authentication and authorization as interchangeable.

Authentication (AuthN) = Who you are
Authorization (AuthZ) = What you’re allowed to do

If you’re building fast—especially with AI tools—make sure you’ve got both covered.