SSL, DNS & Domains Code Audit

Common SSL, DNS & Domain Findings

Certificate expiration without monitoring is the most common finding. Teams configure SSL certificates and forget about them. Let’s Encrypt auto-renewal breaks silently - a DNS change, a firewall rule, a server migration - and nobody notices until the certificate expires and users see browser warnings. This is the most preventable outage in operations.

DNS configuration drift accumulates over time. Records pointing to decommissioned servers. CNAME chains that add latency. Missing AAAA records for IPv6. TTL values that are either too low (excessive DNS queries) or too high (changes take hours to propagate). MX records pointing to old email providers. Each misconfiguration is small. Together, they create fragility.

Security headers are consistently missing. No HSTS, so browsers don’t enforce HTTPS. No Content-Security-Policy, so XSS attacks have no browser-level mitigation. No X-Frame-Options, so clickjacking is possible. These headers take minutes to add and prevent entire categories of attacks.

Our Audit Approach

We inventory every certificate across all domains and subdomains. Expiration dates are documented. Auto-renewal is tested, not assumed - we verify that renewal mechanisms actually work by checking renewal history and testing the renewal process. Monitoring is configured to alert 30 days before expiration.

DNS is reviewed record by record. Every A, CNAME, MX, TXT, and SRV record is validated against current infrastructure. SPF, DKIM, and DMARC are verified for email deliverability. TTL values are assessed for appropriateness. We check for records pointing to resources that no longer exist.

Security headers are tested against Mozilla Observatory and Security Headers standards. Each missing header is documented with the specific risk it creates and the implementation required. CDN configuration is reviewed for caching behavior, edge security rules, and SSL termination settings.

TLS Configuration and Cipher Suite Assessment

Beyond certificate expiration, the quality of your TLS configuration determines your actual security posture. We test cipher suite ordering, protocol version support, and key exchange parameters against current best practices. Servers still offering TLS 1.0 or 1.1 are flagged for immediate remediation - these protocols have known vulnerabilities and are rejected by modern browsers.

We verify that your servers prefer forward-secrecy cipher suites (ECDHE-based) over static RSA key exchange. Forward secrecy ensures that a compromised server private key cannot decrypt previously captured traffic. Certificate chains are validated for completeness - missing intermediate certificates cause failures on some clients while appearing to work on others, creating intermittent issues that are difficult to diagnose.

OCSP stapling configuration is checked to ensure certificate revocation status is served by your server rather than requiring browsers to contact the certificate authority directly. CAA (Certificate Authority Authorization) DNS records are reviewed to prevent unauthorized certificate issuance for your domains. These records specify which certificate authorities are permitted to issue certificates, reducing the risk of misissued certificates from compromised or rogue CAs.

What Changes After the Audit

Certificate management becomes proactive. Monitoring alerts well before expiration. Auto-renewal is verified working. The team never discovers an expired certificate from a user complaint again.

DNS becomes intentional. Every record has a purpose. Email deliverability improves with proper authentication records. Security headers protect against client-side attacks. The invisible infrastructure that users depend on is managed, monitored, and maintained.