Setup Wildcard SSL Certificates

When considering wildcard SSL certificates (e.g., *.example.com) for multi-tenant environments, follow these security best practices:

1. Evaluate if wildcard certificates are necessary for your use case

   • Only use wildcard certificates when there is a specific technical requirement

   • Avoid using them purely for convenience

2. Configure the wildcard certificate scope

   • Apply certificates to specific subdomains rather than the main domain

   • Limit the scope of usage to minimize potential security risks

3. Consider using ACME protocol with automation

   • Implement automated certificate generation using protocols like ACME

   • Use tools like Caddy with ZeroSSL for automated certificate management

4. Plan for key rotation

   • Consider the number of devices that will use the certificate

   • Implement a robust key rotation strategy

Usage

When implementing wildcard certificates in a multi-tenant environment:

• Monitor certificate expiration dates and plan renewals accordingly

• Maintain an inventory of all systems using the wildcard certificate

• Document procedures for certificate updates and emergency replacements

For more detailed guidance, refer to the OWASP TLS Security Cheat Sheet.