v0 by Vercel is superb at generating polished UI fast. That's the strength - and the trap: a great-looking frontend can hide a backend and data layer that were never hardened for real users. We audit what's underneath and fix it.
Run a free 30-second scan Book an auditv0 (v0.dev, rebranded v0.app in January 2026) is Vercel's AI UI/app generator: it turns a prompt into real React, Next.js, Tailwind, and shadcn/ui code with one-click deploy to Vercel. Vercel puts adoption at 6M+ developers as of March 2026. It's used by pro developers prototyping fast, PMs validating ideas, and founders shipping MVPs - often paired with Supabase, Neon, or Vercel Postgres for the data layer. Slick UI creates trust with users and founders alike, which is exactly why the security gaps sitting behind that UI tend to go unnoticed until launch.
v0's own team has been candid about this: its AI policy explicitly disclaims that output "may be inaccurate, biased, unverified, or potentially harmful." Here's what that looks like in practice.
Any env var prefixed NEXT_PUBLIC_ gets bundled straight into the client-side JavaScript, in plain text, for anyone to read. Vercel says it blocked more than 17,000 deployments with exposed secrets in July 2024 alone, and over 100,000 insecure deployments in total since launch - commonly Google Maps, reCAPTCHA, EmailJS, PostHog, Supabase, OpenAI, Gemini, Claude, and xAI keys.
We fix it by moving any real secret out of NEXT_PUBLIC_ entirely, into Route Handlers or Server Actions, and rotating anything already exposed.
Using dangerouslySetInnerHTML or otherwise rendering user-supplied content without sanitizing it first is the top vulnerability class flagged by third-party scanners of v0-style AI-generated frontends.
We fix it with DOMPurify (or equivalent) on anything user-supplied, avoiding dangerouslySetInnerHTML for user content, and a Content-Security-Policy.
v0 is UI-first - it's easy to end up with checks that only exist in the client component, while the actual Route Handler or Server Action behind it never verifies who's calling it or what they're allowed to do.
We fix it by authorizing every Server Action and Route Handler independently of whatever the UI shows.
When a v0 app is wired to Supabase, the anonymous key can end up with read/write access to every row in a table if Row-Level Security was never turned on - a broad, industry-wide pattern in AI-generated apps using Supabase, not unique to any one builder.
We fix it by enabling RLS with per-table policies and keeping the service_role key server-only, never shipped to the client.
Generated API routes rarely ship with any request throttling, leaving signup forms, login attempts, and paid AI calls open to abuse or runaway cost.
We fix it with Vercel WAF rate-limit rules or Upstash/Redis-backed middleware.
This describes the platform, not the code v0 writes for you. Vercel holds SOC 2 Type 2 and ISO/IEC 27001:2022 certification, meets GDPR commitments, and provides a free WAF and DDoS layer platform-wide (it reports blocking 4.4 billion malicious requests a month). Training policy matters if you paste sensitive data into prompts: on the free Hobby tier (including trial Pro) your prompts are opted in to training by default; paid Pro is opted out by default; Enterprise is never used for training. None of this changes whether the app v0 generates for you is secure - that's a separate, code-level question.
| Framework | Status |
|---|---|
| HIPAA | Vercel will sign a BAA as a business associate, but only for "eligible Pro and Enterprise" accounts - must be requested via sales. Hobby has no coverage at all. |
| PCI DSS | Vercel provides SAQ-D (service provider) and SAQ-A (merchant) attestations for its own infrastructure - any v0 app that touches card data directly, rather than through an isolated payment iframe, breaks that scope. |
| SOC 2 / ISO 27001 | Vercel's attestation covers Vercel's infrastructure. It does not certify the security of the application code v0 generated for you. |
v0 is a SaaS product, not a package, so it has no CVE of its own. But it generates React and Next.js App Router code by default, and both have had critical vulnerabilities that unpatched v0 apps can inherit.
| Issue | Severity | What it means for a v0 app |
|---|---|---|
| CVE-2025-29927 - Next.js Middleware Authorization Bypass | Critical | A crafted x-middleware-subrequest header could skip middleware entirely - including auth and CSP checks - on self-hosted `next start` deployments. Vercel-hosted apps were not affected; self-hosted v0 apps on a vulnerable Next.js version were. Fixed in 14.2.25 / 15.2.3+. |
| CVE-2025-55182 "React2Shell" | CVSS 10.0 | Unauthenticated remote code execution via insecure deserialization in React Server Components, affecting React 19.0–19.2.0 and the Next.js App Router - exactly what v0 generates by default. Exploited in the wild within days of disclosure. Fixed in React 19.0.1/19.1.2/19.2.1+. |
| v0 abused for phishing (no CVE) | - | Threat actors have used v0.dev itself to generate convincing phishing pages - including a cloned Okta login page - in about 30 seconds. Not a flaw in your app, but a reason to double-check any "built with v0" link you didn't create yourself. |
Visually, often yes; structurally, usually not. v0 optimizes for how the app looks and feels, not for what's happening on the server. Auth, secrets handling, and database rules typically need a dedicated hardening pass before real users touch it.
It can scaffold API routes and a database connection (often Supabase or Vercel Postgres), but those scaffolds commonly ship without real authorization checks, rate limiting, or Row-Level Security turned on - that's exactly what we check for.
Vercel will sign a BAA, but only for eligible Pro and Enterprise accounts requested through sales - not Hobby. Even with a BAA, the app itself still needs PHI access controls, encryption, and audit logging, which v0 does not generate automatically.
Secrets shipped to the browser through NEXT_PUBLIC_ environment variables. Vercel itself has blocked well over 100,000 insecure deployments for exactly this since launch - it's the single most common mistake we see.
The initial scan is free and takes about 30 seconds. A full audit starts at and any fixes we recommend are quoted separately based on what we actually find in your app.
Free 30-second scan, then a clear list of what needs fixing before real users touch it.
Run a free 30-second scan