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DNSCritical PriorityPro

Subdomain Takeover

Subdomain takeover occurs when DNS records point to deprovisioned external services that attackers can claim.

Why It Matters

Attackers can serve malicious content from your subdomain, steal cookies set for the parent domain, and conduct phishing using your trusted domain.

How We Check

We check for DNS records pointing to external services showing unclaimed resource indicators (404s, 'NoSuchBucket', etc.).

How to Fix

Remove DNS records for decommissioned services before canceling them. Regularly audit subdomains. Use wildcard certificates carefully.

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