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Subdomain Takeover Checker

Check a subdomain for potential takeover by analyzing DNS records and HTTP responses. Detects unclaimed services across AWS, GitHub, Heroku, Azure, and more.

Results

Enter a subdomain URL and click Check.

What is Takeover Checker?

Detect subdomain takeover vulnerabilities. Check for unclaimed services on AWS S3, GitHub Pages, Heroku, and 20+ providers.

Security Guide

Subdomain takeover
Claim orphaned services (Heroku/S3/GitHub Pages) before attackers do
CNAME cleanup
Delete unclaimed CNAME records immediately → Subdomain Scanner
Service claims
Claim orphaned services on AWS S3, GitHub Pages, Heroku, etc. before attackers
DNS monitoring
Monitor CNAME changes — unexpected changes may indicate takeover attempts
Automated management
Use external-dns to prevent stale records → DNS Lookup