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Subdomain Takeover Scanner

Free subdomain takeover scanner and checker — find dangling CNAME records that may allow takeover on common SaaS providers. Instant results, no signup.

  • CNAME fingerprint matching
  • Live response verification
  • Common SaaS provider coverage
Use example.com or https://example.com.

Free online Quick Check — no signup required.

What This Tool Checks

  • CNAME fingerprint matching
  • Live response verification
  • Common SaaS provider coverage

Why It Matters

A subdomain takeover scanner finds forgotten DNS records that still point at decommissioned SaaS or hosting services someone else can claim — impersonating your brand on that hostname.

Best For

Best for teams auditing DNS after vendor offboarding, marketing campaign teardowns, or broader subdomain inventory reviews.

What To Do Next

Remove stale CNAME records or reclaim the upstream service immediately, then add decommissioning checks to your DNS change workflow.

Frequently Asked Questions

A subdomain takeover scanner checks whether DNS still points at a decommissioned SaaS or hosting service that someone else can claim. Vulnify matches CNAME fingerprints and live responses on a domain you own — free Quick Check, no signup.