Netlify

Netlify Security Best Practices

Secure your Netlify deployments with these essential practices. From environment variables to Edge Functions security.

Verify your app follows these best practices automatically.

Netlify handles infrastructure security, but application security is your responsibility. These practices help you deploy securely on Netlify.

Quick Wins

Verify no secrets in git repository
Add security headers in _headers file
Test functions without authentication
Check deploy preview visibility
Review environment variable contexts

Security Best Practices

#1Use Environment Variables for Secrets

critical

Never commit secrets to your repository. Use Netlify's environment variable management.

Implementation

Add secrets in Netlify Dashboard → Site Settings → Environment Variables

#2Scope Variables to Deploy Contexts

critical

Use different secrets for Production, Deploy Preview, and Branch Deploy contexts.

Implementation

Configure context-specific values in Site Settings → Environment Variables

#3Secure Netlify Functions

high

Validate authentication and authorization in every serverless function.

Implementation

Check JWT/session validity and user permissions at function start

#4Configure Security Headers

high

Add CSP, HSTS, and other security headers via _headers file or netlify.toml.

Implementation

Create _headers file in publish directory or add headers to netlify.toml

#5Protect Deploy Previews

high

Deploy previews are public by default. Add protection for sensitive sites.

Implementation

Use password protection or identity-based access control

#6Enable Netlify Graph Security

medium

If using Netlify Graph, restrict which APIs are accessible and validate requests.

Implementation

Configure allowed operations and validate caller identity

Common Mistakes to Avoid

Same environment variables in all contexts

Why it's dangerous:

Exposes production secrets in previews

How to fix:

Use context-specific values for sensitive variables

Missing auth in Netlify Functions

Why it's dangerous:

Anyone with the URL can call your functions

How to fix:

Validate authentication at the start of every function

Public deploy previews

Why it's dangerous:

Preview URLs can leak unreleased features or test data

How to fix:

Enable access control for deploy previews

Verify Your Netlify App Security

Following best practices is the first step. Verify your app is actually secure with a comprehensive security scan.

Scan Your App Free

Frequently Asked Questions

Are my environment variables secure on Netlify?

Yes, Netlify encrypts environment variables and only exposes them to your build and functions. They're not visible in logs or client-side code.

How do I add security headers on Netlify?

Create a _headers file in your publish directory with headers like Content-Security-Policy, or add headers configuration to netlify.toml.

Can deploy previews access production data?

Only if you configure them to. Use context-specific environment variables to ensure previews use staging/test resources.

Last updated: January 2026