Performing SSL Certificate Lifecycle Management

Overview

SSL/TLS certificate lifecycle management encompasses the full process of requesting, issuing, deploying, monitoring, renewing, and revoking X.509 certificates. Poor certificate management is a leading cause of outages and security incidents. This skill covers automating the entire certificate lifecycle using Python and ACME protocol tools.

Objectives

• Generate Certificate Signing Requests (CSRs) programmatically
• Parse and validate X.509 certificates
• Monitor certificate expiration across infrastructure
• Automate renewal using ACME protocol (Let's Encrypt)
• Implement certificate revocation checking (CRL and OCSP)
• Track certificate inventory across multiple domains

Key Concepts

Certificate Lifecycle Stages

1. Request: Generate key pair and CSR
2. Issuance: CA validates and issues certificate
3. Deployment: Install certificate on servers
4. Monitoring: Track expiration and health
5. Renewal: Request new certificate before expiry
6. Revocation: Invalidate compromised certificates

Certificate Types

Security Considerations

• Set up automated monitoring for all certificates
• Use ECDSA (P-256) certificates for better performance over RSA
• Enable OCSP stapling on all servers
• Implement Certificate Transparency log monitoring
• Maintain inventory of all certificates and their locations
• Plan for CA compromise scenarios (key pinning, backup CAs)

Validation Criteria

• CSR generation produces valid PKCS#10 request
• Certificate parsing extracts all relevant fields
• Expiration monitoring detects certificates within threshold
• Certificate chain validation verifies trust path
• OCSP checking detects revoked certificates
• Certificate inventory tracks all deployed certificates