Cookie dan sesi for Next.js
high5 checks
Session cookies are the keys to an account. Missing attributes turn a single XSS bug into full account takeover.
What Next.js must have
- Secure attribute on every cookie
- HttpOnly on session cookies
- SameSite=Lax or Strict on session cookies
- No session identifier in URLs or localStorage
- Session rotation after login and logout invalidation
How to fix it
- 1Set cookie attributes at the framework level so every cookie inherits them
- 2Move tokens out of localStorage to HttpOnly cookies
Next.js context
React framework with server-side rendering, routing and API routes, usually deployed on Vercel or Node.
Server components and middleware carry the auth boundary. Middleware-only auth was bypassable via CVE-2025-29927 — enforce authorisation in the route itself.