Hostname from SSL
Extract hostname from SSL certificate.
- Enter a hostname to fetch a live certificate, or paste a certificate PEM.
- Click Check SANs.
- Review Common Name, SANs list, certificate type, and validity.
-----BEGIN CERTIFICATE-----\nMIIFazCCA1OgAwIBAgIR...\n-----END CERTIFICATE-----
What is Hostname from SSL Extraction?
Hostname from SSL extraction identifies all domain names and hostnames covered by an SSL certificate. This includes the Common Name (CN) and all Subject Alternative Names (SANs), providing a complete picture of which domains the certificate can secure.
This tool is essential for certificate auditing, security assessments, and ensuring proper SSL coverage across your infrastructure. It helps identify potential security gaps and verify certificate deployment accuracy.
Why Extract Hostnames from SSL Certificates?
🔍 1. Security Auditing
Comprehensive security assessment requires knowing all protected domains:
- → Domain Coverage: Verify all intended domains are protected
- → Unauthorized Domains: Identify unexpected domains in certificates
- → Wildcard Scope: Understand wildcard certificate coverage
- → Certificate Inventory: Maintain accurate certificate databases
🛡️ 2. Penetration Testing
Security professionals use hostname extraction for reconnaissance:
- Discover subdomains and services
- Map attack surface and entry points
- Identify internal domain structures
- Find development and staging environments
- Locate forgotten or legacy services
📊 3. Certificate Management
Efficient certificate lifecycle management:
- Track certificate coverage across infrastructure
- Plan certificate renewals and updates
- Identify overlapping certificate coverage
- Optimize certificate consolidation
- Ensure compliance with security policies
🔧 4. Troubleshooting SSL Issues
Diagnose certificate-related problems:
- Verify domain name mismatches
- Check missing subdomain coverage
- Identify certificate deployment errors
- Validate load balancer configurations
Certificate Hostname Types
🎯 Common Name (CN)
Primary domain in certificate subject:
- Main domain the certificate was issued for
- Legacy field, now supplemented by SANs
- Still required for certificate validity
- Example: example.com
📋 Subject Alternative Names (SANs)
Additional domains in certificate extension:
- Multiple domains in single certificate
- Includes subdomains and alternate domains
- Modern standard for multi-domain certificates
- Example: www.example.com, api.example.com
🌟 Wildcard Domains
Pattern-based domain coverage:
- Covers unlimited subdomains at one level
- Uses asterisk (*) as wildcard character
- Cost-effective for many subdomains
- Example: *.example.com covers api.example.com, www.example.com
Common Use Cases
🔍 Security Assessment
Extract hostnames to map an organization's digital footprint, identify exposed services, and assess potential attack vectors during security audits.
📊 Certificate Inventory
Build comprehensive certificate databases by extracting all hostnames, enabling better certificate lifecycle management and compliance tracking.
🚨 Incident Response
During security incidents, quickly identify all domains potentially affected by compromised certificates or infrastructure breaches.
🔧 Migration Planning
Plan infrastructure migrations by understanding current certificate coverage and ensuring all services remain protected after migration.
💡 Best Practices
- ✓ Extract hostnames from all certificates in your infrastructure
- ✓ Document discovered domains for security assessments
- ✓ Cross-reference with DNS records for completeness
- ✓ Monitor for unexpected domains in certificates
- ✓ Use extracted data for certificate consolidation planning
- ✓ Regularly audit certificate hostname coverage
🔗 Related Tools
Complete your certificate analysis workflow: