Security scanning for v0 apps
v0 produces Next.js. That means server routes as well as a bundle — more surface, in both directions.
What a v0 app is made of
- Next.js, usually the App Router
- Server actions and route handlers
- Deployed to Vercel
The server side is the difference
A Next.js app has real server code, which is good — a key can live somewhere the browser never sees. The failure mode is the boundary: a value prefixed NEXT_PUBLIC_ is shipped to the browser, and it is very easy to reach for that prefix when something does not work.
Route handlers also mean real endpoints with real parameters, so the classic web checks matter here in a way they do not on a purely static front end. We map what we can reach, then test it.
The checks that matter here
- Exposed secret / misconfigurationSpecifically anything that crossed the NEXT_PUBLIC_ line.
- Broken access control / IDORRoute handlers that fetch by id without checking who is asking.
- Reflected XSSAnywhere a value reaches a raw-HTML sink.
- Missing security headersSet them once in next.config rather than per route.
What this does not cover
- We test the running application, not your repository. Server code we cannot reach is not covered.
- Server actions invoked only from inside your own UI may not be discoverable from the outside, and the report lists what was actually reached.
Free, no signup, and it reads your bundle. About a minute.
We name v0 because the scanner was built and graded against apps built with it, including a real one we deliberately broke and a real one we built normally. We do not claim a partnership with v0 and we are not endorsed by them.