HOW SECURE IS V0.DEV? (B-)

Rating: B-

v0.dev is safe as a generator. The score reflects consistent gaps in generated code: missing auth guards on forms, no input validation, and no Content-Security-Policy by default. Lower-risk than Bolt because v0 leans frontend-only.

Top failure modes

1. Missing auth on generated forms — Forms POST to endpoints with no auth check because v0 defaults to frontend-only scaffolding.

2. No CSP headers — Generated deployments don’t ship Content-Security-Policy. XSS blast radius larger than it needs to be.

3. Client-side validation only — Input checks live in React; the receiving endpoint trusts whatever the client sent.

How to make v0.dev safer

1. Treat the defaults as a starting point, not a secure configuration.
2. Audit each failure mode above against your specific deployment.
3. Run an automated scan against the deployed app — UI signals rarely surface the backend issues.
4. Re-scan after every material change (new table, new Edge Function, new env var).

For the full analysis of v0.dev’s platform, defaults, and the failure modes we find on real deployments, see Is v0.dev Safe?.

Related

• V0 Security Scanner
• Lovable vs V0 Security

FAQ

Is v0.dev safe to use?

The platform is safe. The generated code is UI-focused and has fewer backend-related failure modes than Lovable or Bolt, but still ships with the standard missing-auth/missing-validation patterns.

Does v0.dev handle authentication?

v0 can generate auth UI, but authentication enforcement is on you — the generated code assumes you’ll add server-side checks before production.

How does v0 compare to Bolt.new on security?

v0 is lower-risk because it’s frontend-first. Bolt generates full apps with backends; v0 generates UI you wire up. Different blast radius.