What Authentication Issues Do Vibe-Coded Apps Have?
Authentication and authorization bugs are the most common critical finding in vibe-coded app audits. AI tools generate login flows that work in the happy path but fail under adversarial conditions. These are the patterns we find most often.
JWT Tokens Decoded But Not Verified
AI-generated code frequently decodes a JWT to read the user ID or role, but skips verifying the signature. This means an attacker can forge any JWT — changing their user ID to 1 to become admin, or changing their role from 'user' to 'admin'. Always verify JWT signatures server-side using the secret key, never just decode the payload.
IDOR: Wrong User Accessing Any Resource
Insecure direct object references (IDOR) are the most common authorization bug. The pattern: GET /api/invoices/12345 returns the invoice — but doesn't check whether the logged-in user owns invoice 12345. Change the ID to 12346 and you get someone else's invoice. AI tools add authentication (you must be logged in) but routinely skip authorization (you must own this resource). Every resource endpoint needs an ownership check.
Admin Routes Protected Only by Login
AI-generated admin panels frequently check isAuthenticated() but not isAdmin(). Any logged-in user who discovers the /admin URL can access it. This pattern appears in Lovable, Bolt, and Cursor-generated apps consistently. Every admin route needs explicit role verification, not just session presence.
Session Tokens Not Rotated After Login
Session fixation attacks work by giving a user a session token before they log in, then waiting for them to authenticate. If your app uses the same session token before and after authentication, an attacker who can set a cookie (via XSS or other means) can hijack any account. Session tokens must be rotated — a new token issued — immediately after successful login.
Password Reset Flows That Can Be Abused
Common password reset bugs in vibe-coded apps: reset tokens that don't expire, reset links that can be reused multiple times, username/email enumeration via different error messages ('user not found' vs. 'email sent'), and reset flows that don't invalidate existing sessions (resetting your password should log out all other devices).
Missing Re-Authentication on Sensitive Actions
High-risk actions — changing email, changing password, deleting account, initiating a transfer — should require re-authentication even from an authenticated session. AI-generated code rarely adds this step. If an attacker gets access to a logged-in browser session (shared computer, stolen cookie), they should not be able to change account details without knowing the password.
How a Code Audit Finds These
A code audit maps your entire authentication and authorization architecture, then systematically tests every path for the patterns above. We also test manually — creating accounts, forging tokens, and attempting to access unauthorized resources — to confirm what the code review identified. Every finding comes with the exact fix needed.