SharkDNS guide
4 min readSubdomain discovery for asset inventory
Use public subdomain data to build a cleaner domain inventory and find exposed hosts.
subdomain findersubdomain discoveryasset inventoryDNS host records
When to use it
Subdomain discovery is useful before audits, migrations, monitoring setup, or security reviews. It helps find public hosts that may not be documented internally.
What to look for
Pay attention to staging, admin, API, mail, CDN, and old application hostnames. These names often explain how a domain is structured and where operational risk may exist.
How to validate
Public feeds can contain stale names. Recheck important hosts with DNS lookup, HTTP status, and certificate data before treating them as active assets.
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