Lovable Apps Look Production-Ready. Then Someone Accesses Another User's Data.

Lovable generates apps that look production-ready. The UI is polished. The components are responsive. The user flows make sense. Then you deploy, and someone accesses another user’s data through an unprotected API.

The gap between “looks ready” and “is ready” is where security issues live.

How Lovable Generates Code

Understanding Lovable’s generation patterns helps predict where vulnerabilities appear.

Lovable Generation Pattern : Lovable’s AI generates full-stack applications using React/Next.js frontends with Supabase backends, optimizing for visual completeness and feature functionality over security implementation.

Lovable typically produces:

React or Next.js frontends with Tailwind CSS
Supabase for database and authentication
Component-based architecture
API routes for backend logic

The code is well-structured. The architecture is reasonable. The security is incomplete.

Common Lovable Security Gaps

1. Unprotected Supabase Queries

Lovable frequently generates direct Supabase queries without proper filtering.

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// What Lovable generates
const { data: todos } = await supabase
  .from('todos')
  .select('*');

// Returns ALL todos from ALL users
// Anyone can see everyone's data

// What you need
const { data: todos } = await supabase
  .from('todos')
  .select('*')
  .eq('user_id', user.id);

// Only returns the current user's todos

2. Missing Row Level Security (RLS)

Supabase provides Row Level Security, but Lovable doesn’t enable or configure it by default.

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-- Lovable creates the table
CREATE TABLE todos (
  id uuid DEFAULT uuid_generate_v4(),
  user_id uuid REFERENCES auth.users,
  title text,
  completed boolean DEFAULT false
);

-- But doesn't add RLS policies
-- Missing: ALTER TABLE todos ENABLE ROW LEVEL SECURITY;
-- Missing: CREATE POLICY for select, insert, update, delete

Without RLS, anyone with the Supabase anon key can query any data directly.

Row Level Security : A PostgreSQL feature that restricts which rows a user can access based on policies you define. Essential for multi-tenant applications where different users should only see their own data.

3. Client-Side Authorization

Lovable puts authorization logic in React components, which is easily bypassed.

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// Lovable-generated component
const AdminDashboard = () => {
  const { user } = useAuth();

  // This check only hides the UI
  // It doesn't prevent API access
  if (user.role !== 'admin') {
    return <Navigate to="/" />;
  }

  return <AdminPanel />;
};

// The admin API routes are still accessible to anyone
// who knows the endpoint

Hiding a button doesn’t protect the functionality behind it.

4. Exposed Environment Variables

Lovable generates environment variable usage that sometimes exposes secrets.

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// Generated API configuration
const supabase = createClient(
  process.env.NEXT_PUBLIC_SUPABASE_URL,
  process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY
);

// This is fine - anon keys are meant to be public

// But sometimes:
const adminSupabase = createClient(
  process.env.NEXT_PUBLIC_SUPABASE_URL,
  process.env.SUPABASE_SERVICE_KEY // Service key in client code!
);

Service role keys bypass RLS entirely. Exposing them gives attackers full database access.

5. Insecure API Routes

Lovable generates API routes without authentication checks.

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// pages/api/users/[id].js
// Generated by Lovable
export default async function handler(req, res) {
  const { id } = req.query;

  const { data: user } = await supabase
    .from('users')
    .select('*')
    .eq('id', id)
    .single();

  res.json(user); // Returns any user's data
}

// No authentication check
// No authorization check
// Full user data exposed

6. Missing Input Validation

Lovable accepts and processes user input without validation.

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// Generated form handler
const handleSubmit = async (formData) => {
  const { title, description, priority } = formData;

  await supabase.from('tasks').insert({
    title,        // No length check
    description,  // No sanitization
    priority,     // Could be any value
    user_id: user.id
  });
};

The Pre-Launch Security Checklist

Lovable Security Checklist

Complete security review for Lovable-generated applications

Enable Row Level Security

For every table in your Supabase project, run:

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ALTER TABLE your_table ENABLE ROW LEVEL SECURITY;

Then create appropriate policies for select, insert, update, and delete operations.

Create RLS Policies

Add policies that restrict data access:

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CREATE POLICY "Users can view own data"
ON todos FOR SELECT
USING (auth.uid() = user_id);

CREATE POLICY "Users can insert own data"
ON todos FOR INSERT
WITH CHECK (auth.uid() = user_id);

Audit Supabase Queries

Search your codebase for supabase.from(. Every query should either:

Filter by user_id (.eq('user_id', user.id))
Be protected by RLS policies
Intentionally return public data

Protect API Routes

Add authentication checks to every API route:

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export default async function handler(req, res) {
  const { data: { user } } = await supabase.auth.getUser(
    req.headers.authorization?.replace('Bearer ', '')
  );

  if (!user) {
    return res.status(401).json({ error: 'Unauthorized' });
  }

  // Continue with authenticated logic
}

Server-Side Authorization

Move authorization checks to the server:

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// Before returning admin data
if (user.role !== 'admin') {
  return res.status(403).json({ error: 'Forbidden' });
}

Client-side checks are for UX, server-side checks are for security.

Verify Environment Variables

Check that:

NEXT_PUBLIC_* variables contain only public information
Service role keys are never in client code
API keys for external services are server-side only

Add Input Validation

Validate all user input:

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const { title, priority } = formData;

if (!title || title.length > 200) {
  throw new Error('Invalid title');
}
if (!['low', 'medium', 'high'].includes(priority)) {
  throw new Error('Invalid priority');
}

Test Authorization Boundaries

Manually test:

Can you access another user’s data by changing IDs in requests?
Can you access admin features without admin role?
Can you modify data belonging to other users?

Review Supabase Dashboard

In Supabase dashboard, check:

All tables have RLS enabled
No public policies that expose sensitive data
Storage buckets have appropriate policies

Add Security Headers

Configure Next.js security headers in next.config.js:

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headers: async () => [{
  source: '/:path*',
  headers: [
    { key: 'X-Content-Type-Options', value: 'nosniff' },
    { key: 'X-Frame-Options', value: 'DENY' },
    { key: 'X-XSS-Protection', value: '1; mode=block' }
  ]
}]

Audit Third-Party Integrations

If Lovable added payment, email, or other integrations, verify:

API keys are stored securely
Webhooks validate signatures
Sensitive data isn’t logged

Configure Error Handling

Ensure production errors don’t expose details:

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if (process.env.NODE_ENV === 'production') {
  res.status(500).json({ error: 'Internal error' });
} else {
  res.status(500).json({ error: err.message, stack: err.stack });
}

Set Up Monitoring

Configure error tracking (Sentry, LogRocket) to catch issues post-launch. Monitor for unusual patterns like bulk data access attempts.

Review Storage Policies

If using Supabase Storage, ensure:

Private buckets require authentication
Upload policies restrict file types and sizes
No path traversal vulnerabilities

Run Automated Scan

Use security scanning tools to catch issues you might have missed. Address all critical and high-severity findings before launch.

Quick Validation Commands

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# Search for unfiltered Supabase queries
grep -r "supabase.from" --include="*.js" --include="*.ts" | grep -v "eq("

# Find potential RLS issues
grep -r "select\(\*\)" --include="*.js" --include="*.ts"

# Check for exposed service keys
grep -r "SUPABASE_SERVICE" --include="*.js" --include="*.ts" | grep -v ".env"

# Find API routes without auth
grep -rL "getUser\|getSession\|auth" pages/api/

Lovable-Specific RLS Templates

Copy these policies for common Lovable patterns:

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-- User-owned data (todos, notes, etc.)
CREATE POLICY "Users manage own data"
ON user_data
FOR ALL
USING (auth.uid() = user_id)
WITH CHECK (auth.uid() = user_id);

-- Team/organization data
CREATE POLICY "Team members access team data"
ON team_data
FOR SELECT
USING (
  auth.uid() IN (
    SELECT user_id FROM team_members
    WHERE team_id = team_data.team_id
  )
);

-- Public read, authenticated write
CREATE POLICY "Anyone can read"
ON public_content
FOR SELECT
USING (true);

CREATE POLICY "Authenticated can create"
ON public_content
FOR INSERT
WITH CHECK (auth.uid() IS NOT NULL);

FAQ

Is Lovable less secure than other AI coding tools?

Lovable’s security profile is similar to other AI tools. The Supabase-specific issues are unique to Lovable’s architecture choices, but the fundamental pattern, functional code without security implementation, is universal across AI coding tools.

Should I avoid Lovable for apps with sensitive data?

No, but you must complete security review before handling sensitive data. Lovable generates a good foundation; it just needs the security layer added manually.

Does enabling RLS break my Lovable app?

It might, initially. Enabling RLS without policies blocks all access. Add appropriate policies immediately after enabling RLS. Test thoroughly after changes.

Can I trust Lovable's authentication implementation?

Lovable typically uses Supabase Auth correctly. The issues are in authorization (who can access what), not authentication (who is the user). Verify both, but focus review effort on authorization.

How do I know if my Lovable app is secure enough to launch?

Complete this checklist. Run an automated security scan. Test authorization boundaries manually. If all checks pass and critical issues are resolved, you’re ready for a soft launch with monitoring.

Conclusion

Key Takeaways

Lovable generates polished UIs with incomplete security implementation
67% of Lovable apps have unfiltered database queries exposing all users’ data
Row Level Security must be manually enabled and configured in Supabase
Client-side authorization in React components doesn’t prevent API access
Service role keys must never appear in client-side code
API routes need explicit authentication checks; Lovable doesn’t add them
Input validation is consistently missing and must be added manually
The 15-point checklist takes ~45 minutes and catches most vulnerabilities
RLS policies are essential for any multi-user Lovable application
Automated scanning catches issues manual review might miss

Lovable’s promise is building apps without code. The reality is building apps without the tedious parts of code. Security isn’t tedious; it’s essential.

Forty-five minutes with this checklist transforms a beautiful-but-vulnerable Lovable app into something actually ready for users. Your users deserve that investment.