Is My Lovable App Secure? (Free Checklist)

by Ryan (Founder)

You built an app with Lovable. It works. Users can sign up, save data, upload files, and maybe even pay you. Now you're staring at the deploy button and wondering whether launching it is a mistake.

The honest answer: possibly, but you shouldn't assume it's secure just because it works or because Lovable generated it.

Lovable is capable of creating secure applications. It gives you real code, managed infrastructure, authentication, integrations with services like Supabase, and project-level security scanning.

That's not the same as guaranteeing that your specific app has the right permissions, the right backend checks, the right secret handling, and the right business rules for your product.

Security depends on how your app was prompted, what integrations it uses, what changed while you were building, and whether the parts users can't see actually enforce the rules the interface implies.

This post is a checklist and set of checks we run as part of our audit process before we tell a founder their Lovable app is ready to meet real users, real data, and real money.

The two words most founders confuse

Almost every serious problem in a Lovable app comes back to one of these two ideas missing or being mixed up.

• Authentication answers "who is this user?" This is what happens when someone signs in with an email and password or a magic link.
• Authorization answers "what is this user allowed to do?" It's the check that says a user can view their own invoice but not somebody else's.

An app can be perfectly authenticated and still have zero authorization.

That's the situation where every signed-in user can read every other user's data. Lovable can generate the sign-in flow easily. It can't always infer, from prompts alone, which data each user/role should be allowed to touch.

Authentication proves a user is who they say they are. Authorization decides what that user is allowed to do in your app.

Keep this distinction in mind as you work through the checklist. Almost every item below is really a question about authorization.

What a real pre-launch review has to cover

Testing that the buttons work isn't a security review. A real review looks at the whole stack:

• The database and its access policies
• Backend and edge functions
• Secrets and environment variables
• File storage
• Payments and webhooks
• APIs and validation
• Dependencies
• Deployment and production configuration
• Business logic that is specific to your product

The checklist below walks through the parts that most often go wrong in Lovable apps. Each section explains the risk in plain terms, gives you an AI prompt you can paste into Lovable to inspect the code, and describes a hands-on test you can run yourself.

1. Row Level Security and cross-user data access

If your Lovable app uses Supabase, Row Level Security (RLS) is the mechanism that keeps one user's rows out of another user's requests. It's the first thing worth checking.

RLS isn't automatic on every table. Enabling it is only step one; the policies themselves have to match your product's actual rules. A table with RLS enabled but a policy of using (true) isn't protected. A table with RLS disabled and exposed through Supabase's generated API may be handing out far more data than you intended.

A basic ownership policy looks like this:

create policy "Users can view their own projects"
on public.projects
for select
using (auth.uid() = user_id);

create policy "Users can create their own projects"
on public.projects
for insert
with check (auth.uid() = user_id);

create policy "Users can update their own projects"
on public.projects
for update
using (auth.uid() = user_id)
with check (auth.uid() = user_id);

The key detail is that access is tied to the authenticated session (auth.uid()) rather than a user_id value the browser sent along with the request.

Practical test. Create two normal user accounts, User A and User B. As User A, create a record and copy its ID from the URL or network tab. Sign in as User B and try to load, edit, or delete that record.

A safe result is that User B receives no data and cannot make the change. Depending on how Supabase, PostgREST, and your application handle the request, this may appear as a 401, 403, an empty result, or a successful response that affects zero rows. Verify the actual data and affected-row count rather than relying only on the HTTP status.

If User B can see or modify User A's data, you have a launch-blocking bug.

Review every Supabase table, view, function, and storage bucket used by this app.

For each resource:

1. Explain whether Row Level Security is enabled.
2. List every existing policy in full.
3. Explain which users can select, insert, update, and delete records.
4. Identify any policy that allows anonymous users or authenticated users to access more data than intended.
5. Check whether users can modify ownership fields such as user_id, account_id, organization_id, role, or is_admin.
6. Check whether storage objects are private and whether users can access files belonging to other users.

Don't make changes yet. Return a clear report first, including the affected tables, the risk, and the exact SQL required to fix each issue.

2. Backend authorization on every sensitive request

A Lovable app usually splits work between the browser and one or more backend or edge functions. The presence of a backend function doesn't make the operation safe. The function still has to establish the user's identity from the session and confirm that user is allowed to do what they're asking to do.

The time-tested rule pros lean on: never trust the client. The browser makes a request, but the backend should decide whether or not it's authorized.

The most common mistake is a backend function that reads a user_id, account_id, role, or project_id directly from the request body and trusts it.

const { user_id, project_id } = await req.json();

await delete_project({
  user_id,
  project_id,
});

The caller can change user_id to anything before sending the request. A safer version derives the user from the session and checks ownership using trusted data from the database.

const authorization = req.headers.get('Authorization');

const {
  data: { user },
  error,
} = await supabase.auth.getUser(
  authorization?.replace('Bearer ', ''),
);

if (error || !user) {
  return new Response('Unauthorized', { status: 401 });
}

const { project_id } = await req.json();

const { data: project } = await supabase
  .from('projects')
  .select('id, user_id')
  .eq('id', project_id)
  .single();

if (!project || project.user_id !== user.id) {
  return new Response('Forbidden', { status: 403 });
}

Practical test. Open the browser's Network tab, perform a normal action, and copy the request. In an API client or the browser console, change one of the identifiers, such as project_id or user_id, and resend the request. Any change the current user is not allowed to make should fail with 401 or 403. If it succeeds, you have missing backend authorization.

3. Frontend role checks aren't a security control

Lovable will often generate an admin dashboard that only appears when the user's role is admin. While it may work as you click through it, that doesn't mean it's secure.

"Nobody will find this" is not security. That's known as "security by obscurity" which is a cardinal sin of secops work.

Hiding a button in the interface (for example, when your frontend detects a logged-in user with the role admin) does nothing to the underlying network call talking to your backend. Anything a signed-in user can attempt from the browser must be re-checked on the server.

{user?.role === 'admin' && (
  <button onClick={delete_all_users}>Delete all usersbutton>
)}

const { user } = await get_authenticated_user(req);

if (!user) {
  return new Response('Unauthorized', { status: 401 });
}

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

if (profile?.role !== 'admin') {
  return new Response('Forbidden', { status: 403 });
}

Practical test. Create a normal user account. While signed in as that user, type the admin URL directly into the address bar. Also open the browser console and try calling the admin backend function using fetch. A safe result is that the server rejects the call, not that the interface simply refuses to render the button.

4. Exposed privileged secrets

Not every key in your project is a secret. Supabase publishable keys and legacy anonymous keys are designed to be used from a browser when the underlying RLS policies are set up correctly. Seeing one of these keys in the frontend isn't automatically a bug.

Privileged keys are different. These must never be shipped to the browser:

• Supabase service_role or secret keys
• Stripe secret keys and webhook signing secrets
• OpenAI, Anthropic, or other AI provider keys
• Email service credentials
• Database connection strings and passwords
• OAuth client secrets

An easy mistake is assuming that anything stored in an environment variable is private. It isn't.

Frontend build tools expose specific environment-variable prefixes to browser code. With Vite, variables prefixed with VITE_ are included in the frontend bundle.

With Next.js, variables prefixed with NEXT_PUBLIC_ are bundled for the browser. Other frameworks may use prefixes such as PUBLIC_.

The exact prefix depends on the framework used by Lovable, but the rule is the same: any variable intentionally exposed to frontend code must be treated as public because it ends up in the JavaScript your users download.

const stripe = new Stripe(import.meta.env.VITE_STRIPE_SECRET_KEY);

const stripe = new Stripe(Deno.env.get('STRIPE_SECRET_KEY'));

The browser should call a protected backend endpoint rather than holding the secret itself.

Practical test. Open your production site (not the Lovable preview), open DevTools, and look at the Sources tab. Search the loaded JavaScript for known credential prefixes such as sk_live, sk_test, and any provider-specific API key formats used by your app.

You can also search for terms such as service_role, SUPABASE_SERVICE, OPENAI, or ANTHROPIC to locate suspicious code, but finding a provider name or environment-variable name alone does not prove that a credential is exposed.

If you find an actual privileged key or token in the frontend bundle, rotate it and move its usage to a backend environment.

Audit this project for exposed credentials and unsafe secret handling.

Check:

- Frontend environment variables, including framework-specific public prefixes such as VITE_, NEXT_PUBLIC_, PUBLIC_, or similar
- Hardcoded API keys and tokens
- Supabase service-role or secret keys
- Stripe secret keys and webhook secrets
- AI provider API keys
- Email service credentials
- OAuth client secrets
- Database connection strings
- Secrets printed to logs or returned in error responses
- Secrets committed in configuration or example files

For every issue, show the file, the type of credential, why it is exposed, and the safest way to move its usage into a backend or edge function.

Don't print complete secrets in your response. Redact all but the first and last four characters.

If a real privileged secret was ever committed or deployed publicly, rotate it. Moving a leaked key into an environment variable doesn't undo the leak.

5. Weak request validation

Your interface may enforce a maximum length on a name, restrict a plan to a fixed set of options, or hide certain fields entirely. Attackers don't have to use your interface (and often don't; they use everything from the browser inspector to specialized tools), they can send whatever they want to your backend directly.

Every sensitive endpoint should independently validate:

• Required fields and their data types
• Accepted values (for example, allowed plan names)
• Minimum and maximum lengths
• Numeric ranges
• File types and sizes
• Redirect destinations
• Any field that affects ownership, roles, pricing, or visibility

const body = await req.json();

await supabase
  .from('profiles')
  .update({
    plan: body.plan,
    role: body.role,
  })
  .eq('id', user.id);

const body = await req.json();

if (
  typeof body.plan !== 'string' ||
  !['free', 'pro'].includes(body.plan)
) {
  return new Response('Invalid plan', { status: 400 });
}

// NOTE: role is intentionally not accepted from the client here.
await supabase
  .from('profiles')
  .update({
    plan: body.plan,
  })
  .eq('id', user.id);

Be especially careful with fields the user isn't supposed to control at all, such as role, is_admin, plan, credits, or stripe_customer_id. The safest pattern is to refuse to accept those from the browser and to set them on the server instead.

6. File uploads and storage policies

File uploads combine several risks: users accessing files that belong to other users, private files that end up publicly readable, unlimited upload sizes, dangerous file types, filename collisions, and storage paths that make it easy to locate or overwrite another user's object when access controls are weak.

A predictable path is not a vulnerability by itself. It becomes dangerous when bucket privacy, storage policies, ownership checks, or signed URL handling fail to prevent unauthorized access.

Both the upload path and the download path have to be reviewed. A private database with a public storage bucket can still leak sensitive customer information.

Audit every file upload and download flow in this app.

Check:

- Maximum upload size
- Allowed file extensions and actual MIME type validation
- Storage bucket privacy (public vs private)
- Row Level Security policies on storage
- File ownership and whether users can read another user's files
- Predictable storage paths and filename collisions
- Users overwriting another user's files
- Public URLs used for files that should require authentication
- [Signed URL](https://supabase.com/docs/guides/storage/serving/downloads#signed-urls) expiration
- Deleted records leaving orphaned files behind
- Dangerous file types (for example, HTML, SVG, or executables)
- User-controlled filenames rendered directly into HTML

Don't make changes yet. Return a table listing each upload flow, the bucket used, who can upload, who can download, and any security issue found. Then provide the exact code or policy changes required.

Practical test. Upload a file that should be private while signed in and inspect the URL or download request your app generates.

Determine whether it is:

• A public object URL
• An authenticated download that requires the user's session or authorization header
• A time-limited signed URL

A public object URL should not load while signed out if the file is meant to be private. An authenticated download should fail without the required session or authorization header.

A signed URL may intentionally work in a signed-out browser until it expires, so also verify that its expiration is appropriately short and that users cannot generate signed URLs for files they do not own.

7. Rate limits and expensive endpoints

Not every security issue is about stealing data. Some are as simple as exposing something to an attacker that's tied to paid resources but lacks a throttle to prevent excessive usage.

The Lovable apps we see almost always have at least one endpoint that:

• Calls an AI provider on every request
• Sends an email
• Generates a large export or PDF
• Triggers a background job

If those endpoints don't require a signed-in user, or if a signed-in user can call them as fast as they want, a single script can drain your API budget in an afternoon.

For every endpoint that touches an external service, ask:

• Does the caller have to be signed in?
• Is the action limited by role or ownership?
• Is there a per-user or per-IP rate limit?
• Is there a maximum input size (for example, prompt length)?
• Can one user consume resources on behalf of another?

Practical test. Sign in as a normal user and send the same request to an expensive endpoint 50 or 100 times in a row from an API client.

The server should begin refusing requests once the intended per-user or per-IP limit is reached. Confirm that the number of accepted requests matches a deliberate usage limit and that rejected requests do not call the paid provider, send additional emails, or enqueue more background work.

Rate limiting cannot prevent every accepted request from incurring a cost, but it should cap how much one user or script can consume within a defined period.

8. Dependencies, logging, and business logic

A Lovable project is still a real software project. It uses packages, custom application logic, and integrations that can inherit any of the ordinary problems every other web application has.

At a minimum, check:

• Vulnerable dependencies. Old versions of common packages with known issues. Lovable's own security scan is a useful first pass; don't treat it as "good enough."
• Sensitive logging. Full request bodies, tokens, or personal information written into logs that other people can read.
• Verbose error responses. Stack traces, SQL errors, and file paths returned to the browser make it easier for someone to map your infrastructure.
• Business-logic flaws. These are the ones scanners can't find. For example: reusing the same coupon repeatedly, approving your own application, viewing another tenant's invoice through a legitimate-looking action, promoting yourself to admin by editing your own profile row.

The last category is where most of the interesting real-world failures live. They look like normal features from the perspective of a user, but under the hood, they have the potential to cause real damage.

9. Deployment and production configuration

Your production environment (what you "deploy" to) isn't the same environment as the Lovable preview. It has its own URL, its own environment variables, its own domain configuration, and often its own quirks.

Things to verify in production specifically:

• HTTPS is enforced and there's no plain HTTP fallback
• The correct environment variables are set (and no development ones leaked over)
• Preview or staging URLs aren't indexed or accepting live traffic
• CORS only allows the origins and request types the endpoint is intended to support. Public, non-credentialed resources may intentionally allow every origin, but authenticated or private endpoints should use a restrictive origin policy.
• Cookies use the Secure and appropriate SameSite settings
• Debug or admin routes from development have been removed or protected

Review the production deployment configuration for this app.

Check:

- Environment variables used in production and whether any development or preview values are present
- HTTPS enforcement and any HTTP fallbacks
- CORS configuration and allowed origins
- Cookie flags (Secure, HttpOnly, SameSite)
- Which routes are publicly reachable in production
- Debug endpoints, seed scripts, or admin utilities left enabled
- Differences between the Lovable preview and the production build

Don't make changes yet. Return a clear report first, including the affected files or settings, the risk, and the exact remediation required.

The adversarial user test

The single most useful hour you can spend before launch is signing in as two ordinary users and trying to make each one do something they shouldn't be allowed to do.

You're not trying to be a penetration tester (a.k.a. "pentester"). You're trying to prove to yourself that the behavior backing the buttons the interface hides are actually enforced on the server.

From a normal user's session, try to:

• View another user's records by loading their record ID
• Edit another user's record by changing an identifier in a request
• Call an admin endpoint directly from the browser console
• Change a role, plan, or ownership field on your own profile
• Access a private file uploaded by another user
• Repeat a payment-related request several times and confirm that it does not create duplicate charges, subscriptions, credits, or records
• Open every authenticated page while signed out

Unauthorized actions should fail on the server. Actions that are legitimately retryable, such as payment requests, should be handled idempotently so repeating the same request does not perform the operation more than once.

Review this app as if you were a malicious but ordinary signed-in user.

Identify any way a user could:

- View another user's data
- Modify another user's data
- Become an administrator by changing their own record or role field
- Access paid features without paying
- Change prices, plans, or entitlement fields
- Call protected backend or edge functions directly
- Abuse AI, email, upload, or export endpoints
- Read private files
- Submit fields that the interface normally hides
- Replay requests or trigger duplicate processing
- Create excessive cost against external services
- Expose secrets or private data through error responses

Trace the frontend request, backend function, database query, and storage policy involved in each sensitive workflow. Don't limit the review to the visible interface.

Don't make changes yet. Return findings ordered by severity, with the attack path, affected files, likely impact, and exact remediation for each one.

Automated scans and coding-assistant reviews

Lovable includes project-level security scanning. Coding assistants can do a decent first pass on your code. Both are useful.

Neither one is a substitute for actually testing your app the way a real user would try to abuse it.

A scanner recognizes patterns it has seen before: a missing policy, a known vulnerable package, a hardcoded key. It generally doesn't understand that your product's rule is only the owner of an organization can invite new members, or that paid access should only turn on when a specific Stripe event arrives with a verified signature. Those are business rules unique to your app, and they're exactly where the most damaging bugs hide.

Automated tools are great for catching the obvious things quickly, but you shouldn't rely on them solely to determine if your app is "secure." That still requires testing your app from the perspective of an attacker and poking holes in your own security.

Is Lovable itself insecure?

No. Lovable can generate authentication, integrate with Supabase, manage deployment, and scan projects for common issues. It's more than sufficient for generating production applications when the resulting app is configured correctly and proper attention has been given to the checklist items outlined above.

The catch is that a platform, however capable, can't always infer every security rule your specific business needs. It can't always know which data each role should access, which action requires ownership, which payment event should grant access, or which edge case would create a meaningful vulnerability for your product.

AI can help you move quick, but rushing an app out the door with uncertain security and behavior can lead to headaches that distract you from serving your customers and hurt your business.

The same is true of applications written by a developer from scratch. The difference is that Lovable makes it possible to build a lot of software very quickly, which makes reviewing the finished software before launch even more important.

The pre-launch security checklist

At an absolute minimum, work through this checklist and verify each of these areas before you send real users to your Lovable app.

How to prioritize what you find

Not every finding is equally urgent. Founders sometimes freeze because a scan reports fifty warnings; sometimes they launch anyway because "nothing broke." Both reactions are avoidable when the findings are grouped by impact.

Don't launch yet if...

We consider these the most serious issues to check for in a Lovable app. These are non-negotiables:

• One user can read or modify another user's data
• A privileged secret is in the frontend bundle or was ever deployed publicly
• The browser can decide whether a user has paid
• Admin actions can be triggered without a server-side authorization check
• Files that should be private are publicly downloadable
• Sensitive tables have RLS disabled or use overly broad policies

Fix these soon...

These are items that need attention, but less urgently than the items above. These are best fixed ASAP:

• Expensive AI, email, or export endpoints have no rate limit
• Error responses expose stack traces or internal detail
• File upload restrictions are incomplete
• Known vulnerable dependencies are in use
• Duplicate requests can create repeated records or charges
• Weak or missing validation on non-privileged inputs

Keep an eye on...

These are important operational protections that should be in place before launch when they apply, then monitored and maintained after launch:

• Access rules continue to be tested as new tables, roles, and workflows are added
• Privileged secrets remain on the server and are rotated when necessary
• Payment events continue to require valid signatures and server-side verification
• Logs avoid sensitive data
• Dependency and security scans run on a schedule
• Production monitoring and alerting are in place

These may not represent an immediate vulnerability at the moment you review them, but they can become serious as the application changes. Treat them as ongoing security responsibilities rather than one-time checks.

Get your Lovable app audited before launch

Fortivibe audits Lovable apps end to end. We look at the actual repository and configuration, run static analysis, and add expert review across authentication, authorization, database policies, secrets, payments, storage, APIs, dependencies, and deployment. You get a written report of concrete findings, why each one matters, and exactly what to change.

You don't need to understand the whole codebase yourself. You just need to know what has to be fixed before real users, real data, and real payments are involved.