Cursor App Security Checklist: 10 Things to Check Before You Ship

Quick answer: Before shipping a Cursor-built app, review secrets, database access, server-side authorization, input handling, errors, dependencies, browser headers, CORS, and session management. Test the controls relevant to your architecture and investigate deployed findings; a working interface does not establish that private data and actions are protected.

By Paula C · Kraftwire Software

Use this checklist to review secret handling, database access, server-side permissions, input validation, errors, dependencies, browser headers, CORS, and sessions. Match each control to the application’s architecture and intended access rules. The checklist does not establish that every security risk has been addressed.

Why Do Cursor Apps Need a Security Checklist?

Cursor can help edit code and run development tasks. Review the permissions of the tools you enable separately from the security of the application they produce.

Inspect permission checks in generated code and test both allowed and denied requests. A functioning feature does not show whether those checks are correct.

Use this checklist to organize manual and automated checks before deployment.

The 10-Point Cursor App Security Checklist

1. Scan for Exposed API Keys and Secrets

Inspect generated code and deployed configuration directly instead of assuming that development settings suit production. Investigate the finding’s impact and severity in your application.

• Check: Inspect matches for sk_live, AIza, service_role, or eyJ (JWT) in their context; a prefix alone does not establish that a value is a secret.
• Fix: Keep secrets in server-side configuration. A .env file is not private if its values enter the client bundle. SimplyScan’s secret scanner checks supported repository inputs and bounded history for recognized patterns.
• Respond: Revoke and replace exposed credentials, then review their use and affected repository history.

2. Verify Row-Level Security (RLS) Policies

For Supabase or PostgreSQL, review privileges, RLS state, policies, and bypass roles. Enabled RLS without applicable policies denies access to roles subject to it; disabled RLS leaves table privileges to govern access.

• Check: A permissive SELECT policy whose USING expression is true allows rows through that policy; privileges and other applicable policies still affect access.
• Fix: For privately owned rows, auth.uid() = user_id can express ownership. Shared records need the intended membership or role rules. Test them with the relevant identities. See the RLS guide.

3. Audit Authentication Guards on Routes

Test server-side authentication and authorization for each protected operation.

• Check: Test protected endpoints both without a session and with an identity that lacks permission.
• Fix: Enforce authentication and authorization at the server or database boundary. A redirect to /login can guide the UI but does not secure the underlying operation.

4. Client-Side vs Server-Side Authorization

A UI condition such as if (user.isAdmin) { return <AdminPanel /> } controls rendering. It does not authorize the API calls made by the panel.

• Check: In an authorized test environment, verify that a non-admin cannot perform the protected action behind /api/delete-user.
• Fix: Enforce the required permission using a trusted identity. Public endpoints may intentionally allow anonymous access; protected operations must not trust a client’s claim of authority.

5. Validate All User Inputs

Review input handling and output use, and test how untrusted data reaches interpreters or the browser. See code injection.

• Check: Test input types and size limits. An input such as ' OR 1=1 -- should remain data rather than alter a database query; an error alone does not prove injection.
• Fix: Use schemas for expected types, lengths, and formats, and parameterized APIs at query boundaries. Input validation does not replace those boundaries.

6. Review Error Handling and Information Leaks

Inspect API errors for exposed credentials, stack traces, internal paths, or database details that the caller does not need.

• Check: Submit malformed test input and inspect the response.
• Fix: Use appropriate error handling, including try/catch where needed. Return useful validation errors without internal details, and restrict server logs so they do not retain secrets or unnecessary personal data.

7. Audit Dependencies for Vulnerabilities

Review the purpose, version, and known vulnerabilities of each dependency regardless of how it was added.

• Check: Run npm audit or pnpm audit and investigate affected versions and usage.
• Fix: Apply and test appropriate updates or mitigations. Remove unused dependencies, and review the compatibility and security impact of each change.

8. Configure Security Headers

Inspect policies such as Content-Security-Policy (CSP) and Strict-Transport-Security (HSTS) on deployed responses. Their behavior depends on configuration and browser support; header presence or absence alone does not establish exploitability.

• Check: Use our security headers tool to check your live URL.
• Fix: If using Next.js or Vercel, configure these in next.config.js or vercel.json.

9. Review CORS Configuration

A header assignment such as res.setHeader('Access-Control-Allow-Origin', '*') permits browser reads of non-credentialed responses from any origin. That may be intentional for public data. For private data, review authentication, authorization, and permitted origins separately.

• Check: Inspect the configured Access-Control-Allow-Origin behavior.
• Fix: Use * only where public non-credentialed access is intended. For restricted browser access, allow the exact required origins, such as https://myapp.com, and test credential handling. CORS does not authenticate a caller or block all cross-origin requests.

10. Test Session and Token Management

Review how the app stores session credentials. Tokens in localStorage are readable by scripts running in the same origin, so an XSS flaw may expose them.

• Check: Inspect storage, cookie attributes, expiration, and revocation behavior.
• Fix: For cookie-based sessions, httpOnly restricts script access to the cookie value and Secure restricts transmission to secure connections. Add appropriate CSRF defenses; these attributes do not stop malicious script from making authenticated requests.

Beyond Security: Speed and AI Visibility (AEO)

Measure performance and inspect discoverability separately from security findings. Each review answers a different question.

For Answer Engine Optimization (AEO), inspect crawler access, available page text, and structured data. The AI visibility tool checks selected signals; it does not establish whether a particular engine will index or cite the app.

Add Automated Checks to the Review

SimplyScan’s free URL scanner checks selected public exposures. Use its findings alongside source review and tests of the application’s intended permissions.

Scan

Enter the deployed URL for checks across eight categories, including selected security, speed, and compliance signals, in about 30 seconds. A scan does not establish legal compliance or complete security coverage.

Review

Get a grade and a prioritized list of fixes.

These live figures describe all scanned sites. They do not establish prevalence for an AI-built subgroup, compare development methods, or attribute findings to AI generation.

The average security score across the 119 live sites SimplyScan has scanned is 86 out of 100.

Monitor

Pro Monitoring includes Pro scan credits for full reports. See pricing for the allowance associated with your chosen option.

Use Pro Monitoring for uptime alerts, including Slack delivery, and scheduled rescans with change alerts. Investigate reported changes and separately repeat tests of signed-in data access.

Run a Free Scan on Your Cursor App →

FAQ

Is code generated by Cursor safe to deploy without review?

Review generated code and deployed behavior before relying on them. Test permissions, secret handling, and other controls relevant to the app. The aggregate scan corpus does not establish Cursor’s model priorities or the prevalence of its mistakes.

How do I fix an exposed API key that Cursor hardcoded?

Revoke and replace an exposed credential through the provider, then check usage and update the server-side configuration. Review repository history and coordinate any cleanup with collaborators; rewriting history does not erase copies already obtained or replace revocation.

How should I review RLS in a Cursor-built app?

For a Supabase or PostgreSQL backend, review privileges, RLS state, and the policies applicable to each role. Enabled RLS with no applicable policy denies access to roles subject to it; bypass roles are different. Test both permitted and denied operations rather than assuming generated policies are correct. Inspect each generated CREATE POLICY statement in that context.

Can I trust Cursor with sensitive company data?

Cursor states that Privacy Mode prevents its training on your data and offers a SOC 2 Type II attestation through its trust portal. Review the current data-handling terms and your organization’s requirements before providing sensitive information. These platform controls do not establish that generated application code is secure.

Which security flaw in "vibe-coded" apps should I check?

Test access control by exercising permitted and denied operations. A hidden admin page does not restrict the underlying API unless the server checks the caller’s permission for the action.

How can I make my Cursor app faster for better SEO?

Measure the affected requests and resources before optimizing. Review image sizes, shipped JavaScript, caching, and server response time as relevant to the measurements. Improved performance does not guarantee search ranking or answer-engine citation.

30% of the 119 live sites SimplyScan has scanned (36 sites) have at least one high or critical security issue.

29% of the 119 live sites SimplyScan has scanned (35 sites) have at least one medium-severity web-security issue, such as a missing Content-Security-Policy or HSTS header.

79% of the 119 live sites SimplyScan has scanned (94 sites) have at least one medium-severity speed issue, such as render-blocking scripts or no route-based code splitting.