Replit + PostgreSQL Security
Replit's PostgreSQL integration is convenient, but database security requires careful credential management and access control.
Why Replit + PostgreSQL?
Replit offers built-in PostgreSQL for projects that need a relational database without Supabase's additional features.
Common Vulnerabilities
These are the security issues we find most often in Replit apps using PostgreSQL.
Connection String Exposure
PostgreSQL connection strings may be hardcoded in public Repls.
No Row Level Security
PostgreSQL RLS exists but is rarely configured in Replit projects.
Missing SSL Connection
Database connections may not require SSL, allowing interception.
Weak User Permissions
Database user may have more permissions than needed.
What We Check for Replit + PostgreSQL
Credential Management
Verify connection strings are in Secrets, not code.
Connection Security
Check that SSL is required for database connections.
Access Control
Review database user permissions and RLS policies.
Query Security
Check for SQL injection vulnerabilities in queries.
Quick Security Wins
Apply these fixes right now to improve your security.
Move DATABASE_URL to Replit Secrets immediatelyRequire SSL: add ?sslmode=require to connection stringEnable RLS on tables: ALTER TABLE t ENABLE ROW LEVEL SECURITY;Use parameterized queries to prevent SQL injectionCreate a limited database user instead of using the adminThe Bottom Line
Replit + PostgreSQL works well when credentials are properly managed. Use Secrets, enable SSL, and consider RLS for multi-tenant apps.
Secure Your Replit + PostgreSQL App
Find Row Level Security misconfigurations, exposed credentials, and other vulnerabilities before attackers do.
Start Security ScanFrequently Asked Questions
Is my PostgreSQL connection string safe in a public Repl?
No, if it's in your code. Connection strings contain passwords and host information. Move it to Replit Secrets immediately. Even in private Repls, hardcoding credentials is bad practice - use environment variables accessed via process.env.
Does Replit's PostgreSQL have Row Level Security?
Yes, PostgreSQL supports RLS natively. Enable it with ALTER TABLE tablename ENABLE ROW LEVEL SECURITY, then create policies. This is especially important for multi-tenant apps where users should only see their own data. RLS works at the database level regardless of your application code.
How do I enable SSL for PostgreSQL connections in Replit?
Add ?sslmode=require to your connection string: postgres://user:pass@host:5432/db?sslmode=require. This encrypts data in transit. Without SSL, database traffic could be intercepted on the network.
How do I prevent SQL injection in my Replit PostgreSQL app?
Always use parameterized queries, never string concatenation. Bad: `SELECT * FROM users WHERE id = ${userId}`. Good: `client.query('SELECT * FROM users WHERE id = $1', [userId])`. ORMs like Prisma or Drizzle handle this automatically.