Cursor App Security Checklist: 10 Things to Check Before You Ship
10 security checks every Cursor-built app must pass before shipping. From exposed keys to missing auth guards, this checklist covers the vulnerabilities AI coding assistants consistently miss.
By Paula C · Kraftwire Software
· 9 min readWhy Cursor Apps Need a Security Checklist
Cursor has become the go-to AI coding IDE for developers who want speed without leaving their familiar VS Code workflow. Its AI assistant generates entire features, refactors code, and writes tests - all from natural language prompts. The productivity gains are real.
But Cursor's AI has the same fundamental limitation as every other code generation tool: **it optimizes for making things work, not for making things secure**. The code it generates is functional, well-structured, and often elegant - but it consistently misses security considerations that an experienced security engineer would catch immediately.
After scanning hundreds of Cursor-built applications through SimplyScan, we've identified the 10 most critical security checks that Cursor apps consistently fail. Use this checklist before every deployment.
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The 10 Essential Security Checks
1. Scan for Exposed API Keys and Secrets
**What to check:** Search your entire codebase for hardcoded credentials. Cursor's AI often places API keys directly in source files when implementing integrations.
**Common patterns to search for:**
`sk_live_` or `sk_test_` (Stripe keys)
`sk-` followed by alphanumeric characters (OpenAI keys)
`service_role` (Supabase service role key)
`Bearer ` followed by a token
`password`, `secret`, `apiKey`, `api_key` in variable assignments
Any string that looks like `eyJ...` (JWT tokens)
Database connection strings (`postgres://`, `mongodb://`, `mysql://`)
**How to fix it:**
Move all secrets to environment variables
Use `.env` files locally and platform-specific secrets managers in production
Prefix only truly public keys with `VITE_` (or your framework's equivalent)
If a secret was ever in source code, rotate it immediately
Add a pre-commit hook to scan for secrets before they enter version control
**Why Cursor misses this:** When you ask Cursor to "add OpenAI integration," it generates working code - which means placing the API key where it can be used. The AI doesn't distinguish between development convenience and production security.
2. Verify Row-Level Security (RLS) Policies
**What to check:** If your app uses Supabase (or any PostgreSQL database with RLS), verify that every table has appropriate RLS policies.
**Common issues in Cursor apps:**
RLS enabled but no policies defined (blocks all access, leading developers to disable RLS entirely)
Policies that use `true` for the USING clause (allows anyone to read all data)
Missing policies for UPDATE and DELETE operations
Policies that check `auth.uid() IS NOT NULL` instead of `auth.uid() = user_id`
**How to fix it:**
Check every table's RLS status and policies
Each table needs at least SELECT and INSERT policies scoped to `auth.uid()`
Add UPDATE and DELETE policies that verify ownership
Use security definer functions for complex role checks
Test by attempting to access other users' data through the Supabase client
3. Audit Authentication Guards on Routes
**What to check:** Every route that displays or modifies user data must require authentication. Cursor often builds pages without auth guards when you don't explicitly mention authentication in your prompt.
**Routes that commonly lack auth:**
`/dashboard` - displays user-specific data
`/settings` - allows account modifications
`/admin` - admin functionality
`/profile/:id` - user profile pages
API routes that return or modify data
**How to fix it:**
Create a reusable auth guard component or middleware
Wrap all protected routes in the auth check
Verify auth on both the client (for UX) and server (for security)
Handle loading states while checking auth to prevent content flash
Redirect unauthenticated users to the login page
4. Check Client-Side vs Server-Side Authorization
**What to check:** Cursor frequently implements access control in React components rather than enforcing it at the database or API level.
**Red flags to look for:**
`if (user.role === 'admin')` in JSX conditional rendering
Role checks using localStorage or sessionStorage values
Feature flags stored in client-side constants
API calls that don't include auth headers
**How to fix it:**
Move all authorization to RLS policies, middleware, or Edge Functions
Use database-level role checks with security definer functions
Store roles in a protected table with proper RLS (not in localStorage)
Client-side checks should only affect UI display, never actual access
5. Validate All User Inputs
**What to check:** Every form, API endpoint, and URL parameter should validate its input before processing.
**Common input validation gaps:**
Form submissions accepted without type or length checking
API endpoints that trust client-sent data without validation
URL parameters used directly in database queries
File uploads accepted without type or size restrictions
**How to fix it:**
Use a validation library (Zod for TypeScript, Joi for JavaScript)
Define schemas for every API endpoint and form
Validate on both client (for UX) and server (for security)
Set maximum lengths for all string inputs
Sanitize HTML content with DOMPurify before rendering
6. Review Error Handling and Information Leaks
**What to check:** Cursor generates the "happy path" - what happens when everything works. But error states often leak sensitive information.
**Information commonly leaked in errors:**
Database table and column names
File paths and server directory structure
Stack traces with function names
API endpoint URLs and parameters
Third-party service details
**How to fix it:**
Add try/catch blocks around all async operations
Return generic error messages to the client ("Something went wrong")
Log detailed errors server-side only
Set up global error handlers for uncaught exceptions
Never include error.stack or error.message in API responses
7. Audit Dependencies for Known Vulnerabilities
**What to check:** Run `npm audit` to check for packages with known CVEs. Cursor installs packages based on AI suggestions, and these may be outdated or have security issues.
**How to fix it:**
Run `npm audit` and address all high/critical findings
Update packages to their latest secure versions
Remove unused dependencies (reduce attack surface)
Check that installed packages are the correct ones (watch for typosquatting)
Set up automated dependency scanning in your CI/CD pipeline
8. Verify Security Headers Are Configured
**What to check:** Test your deployed app's response headers. Most Cursor apps ship without any security headers.
**Required headers:**
`Content-Security-Policy` - prevents XSS attacks
`Strict-Transport-Security` - enforces HTTPS
`X-Frame-Options` - prevents clickjacking
`X-Content-Type-Options: nosniff` - prevents MIME sniffing
`Referrer-Policy` - controls information leakage
**How to fix it:**
Configure headers in your hosting provider (Vercel, Netlify, etc.)
Use the `helmet` middleware for Express applications
Start with strict policies and loosen only as needed
Test at securityheaders.com after deployment
9. Check CORS Configuration
**What to check:** Verify that your API only accepts requests from authorized origins. Cursor often sets CORS to `*` (allow all) to avoid development errors.
**How to fix it:**
Replace `*` with your specific frontend domain(s)
Never combine `*` with `credentials: true`
Test by making requests from an unauthorized origin
Use an allowlist approach for multiple authorized domains
10. Test Session and Token Management
**What to check:** Review how your app handles user sessions, authentication tokens, and logout flows.
**Common issues:**
Tokens stored in localStorage (vulnerable to XSS)
Tokens that never expire
No session invalidation on password change
Missing logout functionality or incomplete session cleanup
**How to fix it:**
Use httpOnly cookies for sensitive tokens
Set reasonable expiration times (1 hour access, 7 days refresh)
Invalidate all sessions when the password changes
Implement proper logout that clears both client and server sessions
Rotate refresh tokens on each use
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Your Pre-Deployment Workflow
**Generate with Cursor** - Build your features
**Code review** - Read the generated code, check for logic issues
**Run this checklist** - Check all 10 items manually
**Scan with SimplyScan** - Automated check of your deployed app
**Fix findings** - Address any issues found
**Re-scan** - Verify fixes with another scan
**Deploy to production** - Ship with confidence
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Automate the Checklist
Manually checking all 10 items takes expertise and time. SimplyScan automates the process - enter your app URL and get results across 14 categories and 51+ checks in 30 seconds.
[Scan your Cursor app now →](/)