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TLS

TLS and Certificate Posture

NullFault observes HTTPS behavior and certificate details that affect whether browsers can trust the production connection.

What NullFault Checks

  • Whether the production target is reachable over HTTPS after redirects.
  • Whether certificate validity and hostname coverage look correct from the scanner's perspective.
  • Whether transport hardening appears present on the live response.

Why It Matters

  • TLS problems can block users, break integrations, and undermine every other security control.
  • Certificate or redirect mistakes often happen during domain moves, CDN setup, and launch-week DNS changes.
  • Transport posture also affects user trust signals in browsers and automated clients.

Common Causes

  • Certificate not covering the www or apex hostname users actually reach.
  • HTTP not redirecting to HTTPS consistently.
  • Mixed canonical domains after a CDN or domain migration.

Check it yourself

Load your site over http:// and confirm it redirects to https://, then click the browser padlock to confirm the certificate matches the hostname.

Mitigation

  • Use a valid certificate covering every production hostname users can reach.
  • Redirect HTTP to HTTPS consistently and avoid mixed canonical domains.
  • Enable HSTS only after confirming HTTPS works across every intended hostname.
  • Monitor certificate renewal and CDN configuration as part of release operations.

Reality check

TLS findings reflect what the scanner observed externally. DNS propagation, regional CDN behavior, and launch-week changes can affect results.

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