26zl 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.
When to Use
- When conducting security assessments that involve performing ssl certificate lifecycle management
- When following incident response procedures for related security events
- When performing scheduled security testing or auditing activities
- When validating security controls through hands-on testing
Prerequisites
- Familiarity with cryptography concepts and tools
- Access to a test or lab environment for safe execution
- Python 3.8+ with required dependencies installed
- Appropriate authorization for any testing activities
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
- Request: Generate key pair and CSR
- Issuance: CA validates and issues certificate
- Deployment: Install certificate on servers
- Monitoring: Track expiration and health
- Renewal: Request new certificate before expiry
- Revocation: Invalidate compromised certificates
Certificate Types
| Type | Validation | Use Case |
|---|---|---|
| DV (Domain Validation) | Domain ownership | Websites, APIs |
| OV (Organization Validation) | Domain + org identity | Business sites |
| EV (Extended Validation) | Full legal verification | E-commerce, banking |
| Wildcard | *.domain.com | Multi-subdomain |
| SAN/UCC | Multiple domains | Multi-domain hosting |
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