Is v0 Safe? Security Risks and the Checklist Before You Ship

You built your app with v0, Vercel's AI builder, and it came together fast. The UI looks sharp, the features work, and you're getting ready to put it in front of real users. Then the doubt arrives: is v0 safe to ship a real app on, or did the AI leave your users' data exposed somewhere you can't see?

It's a sensible thing to ask before launch. v0 is a strong tool from a serious company, and the apps it produces work well. But "works in preview" and "safe in front of strangers" aren't the same thing — and most of v0's users are in the group most likely to miss the difference. Across the vibe-coding world, roughly 63% of users are non-developers, smart people shipping real products without a security background.

Here's the reassuring part: v0 the tool isn't the problem. The risk lives in the backend it wires up — often Supabase — and in a few specific settings the AI doesn't reliably get right. This post shows you where those gaps are and gives you a checklist to run before you ship.

⚡ TL;DR

• v0 is safe to build on. The risk is the backend it generates — frequently Supabase — and whether its tables have proper Row Level Security (RLS = a per-user filter on every database query).
• The most common v0 gap is missing or "allow everyone" RLS, plus secret keys leaking into the frontend. This is the same pattern behind CVE-2025-48757, which found about one in ten AI-built apps leaking real user data this way.
• Your Supabase anon key being public is not a bug — it's meant to ship in the browser. The fix is RLS policies, not rotating the key.

Is v0 safe? The short answer

Yes, with a caveat that does the real work.

v0 is a legitimate tool built by Vercel, and the code it generates isn't malicious or broken. When founders ask "is v0 safe," they're usually picturing the wrong risk. The danger isn't that v0 does something underhanded. It's that v0, like every AI builder, optimizes for making the feature work in the preview — not for controlling who can reach your data once it's live.

Those are different jobs. An app can look polished, work perfectly in the demo, and still leave its database open to anyone who asks. The gap is invisible right up until someone goes looking for it.

So the honest answer: v0 is safe to build on, but the app it hands you isn't automatically safe to ship. The difference comes down to a handful of settings — and you can check and fix every one.

The real risks when you build with v0

v0 commonly wires up Supabase as the backend. Supabase is excellent and is the default across the vibe-coding world, but it ships with a permission model your AI has to configure correctly. Here's where it tends to slip.

Missing or permissive RLS (the big one)

This is the central risk for a v0 app, so it gets the most space here.

Supabase apps talk to the database directly from the browser. There's usually no backend server in the middle asking "is this person allowed to see this?" The database itself is the gatekeeper, and the feature that enforces the rules is RLS (Row Level Security) — an automatic WHERE clause the database adds to every query, deciding which rows each user can see.

When RLS is off, or when a policy is set to USING (true) (which means "match every row" — effectively no protection), any visitor can pull the entire table. Everyone's data, not just their own.

Why does this happen on v0? Because a table with RLS switched off works perfectly in the preview. You can read and write rows, the app looks done, nothing complains. The hole only shows up when an outsider queries your public API directly. We go deep on this in Supabase RLS explained.

This pattern is well documented. The first published CVE for this category, CVE-2025-48757, came from scanning AI-built apps and finding 170 of 1,645 (about 10.3%) leaking user data through missing or USING (true) RLS. That study focused on Lovable apps, but the same root cause recurs on v0, Bolt, Cursor, and Replit — they all share the browser-to-database architecture. There's no separate documented v0 incident; the risk is the shared default, and it's the one to check first.

Exposed secret keys

v0 apps connect to other services — Stripe, OpenAI, email providers. The risk is a secret key ending up in the frontend code that ships to the browser. Keep the distinction clear:

• A Supabase anon key and a Stripe publishable key (pk_live_...) are meant to be public. Not emergencies.
• A Supabase service_role key, a Stripe secret key (sk_live_...), or an OpenAI key in client code is an emergency. The service_role key especially — it bypasses RLS entirely, so anyone who finds it owns your whole database.

This is a common v0 trap because the AI may call a paid API directly from the client to make a feature work quickly. If it does, the secret is likely readable in your JavaScript bundle. See exposed secrets and API keys in frontend code.

Open storage buckets

If your app lets users upload files, v0 may have set up a Supabase storage bucket. Buckets have their own access rules, separate from your tables. A public bucket means its files can be listed and downloaded by anyone with the URL pattern, even when your tables are locked down. It's an easy blind spot because storage feels like a separate system from the database. See Supabase storage bucket security.

Missing security headers and CSRF protection

AI builders rarely set security response headers or CSRF (Cross-Site Request Forgery) protection. A December 2025 study of 15 AI-built apps found zero implemented CSRF protection and zero set security headers. v0 apps inherit the same tendency. Lower-severity than an open database, but worth closing before launch.

How to check your v0 app

You can sanity-check the important things in about ten minutes.

1. Open your Supabase dashboard → Authentication → Policies (or Database → Tables). Every table holding user data should show RLS enabled. A table with real data and "RLS disabled" is your most likely leak.
2. Read the policy, not just the toggle. A table with RLS on but a USING (true) policy looks safe and isn't. Confirm policies use real conditions like auth.uid() = user_id. See the USING(true) trap if that's new to you.
3. Hunt for secret keys in your frontend. In browser dev tools, search your loaded JavaScript for service_role, sk_live, and any AI provider key prefix. None should appear. (An anon key is expected and fine.)
4. Check your storage buckets. In Supabase → Storage, confirm buckets with private files aren't set to public.
5. Test as an anonymous user. Query your public API with only the anon key and see what comes back. If you can read other people's rows, so can anyone.

The pre-ship checklist for v0

Run through this before real users touch your app.

• RLS enabled on every table that holds user data — no exceptions.
• Policies use real conditions, like auth.uid() = user_id, never USING (true).
• No secret keys in the frontend: no service_role, no sk_live_..., no raw AI provider keys in client code. Route those through a server function.
• Storage buckets locked down: private files in private buckets, with access policies.
• Tested as a stranger: you've queried your live endpoints anonymously and confirmed you can't read other people's data.
• Security headers and CSRF protection added where your stack supports them.

A useful move: paste a prompt back into v0 like "Enable RLS on every table that stores user data and add policies so each user can only read and write rows where user_id equals their auth.uid(). Do not use USING(true). Make sure no secret keys are exposed in client-side code; route paid API calls through a server function."

FAQ

Is v0 secure enough for a production app with paying users?

Yes, as long as you configure the backend correctly. v0 can power a production app, but you're responsible for confirming RLS is enabled with real policies, no secret keys ship in the browser, and storage buckets are locked down. The platform doesn't guarantee these by default — you verify them before launch.

Is my v0 app leaking data right now?

Possibly, if it has tables without proper RLS or a secret key in the frontend. The CVE-2025-48757 study found about one in ten AI-built apps leaking through missing RLS, and v0 apps share the same architecture. The way to know is to check your table policies, search your bundle for secret keys, and test your live endpoints as an anonymous user.

Do I need to rotate my Supabase anon key in a v0 app?

No. The anon key is public by design — it's meant to live in your frontend, and Supabase built its permission model around that. Rotating it changes nothing about your security. The key you must never expose is the service_role key.

The bottom line

v0 is safe to build on, and the tool isn't doing anything wrong. The risk is the one every AI builder carries: it optimizes for "it works," not "it's locked down," and the gaps it leaves — missing RLS, USING (true) policies, exposed secret keys, open buckets — are invisible until someone goes looking. An attacker can find an unprotected table or an exposed key in minutes. The job is to find it first, and to keep checking, because v0 ships new code (and potentially new gaps) every time you add a feature.