Free Subdomain Takeover Checker
Identify orphaned DNS records and provider fingerprints that allow takeovers.
Find risky CNAMEs and misconfigurations before attackers do.
- Orphaned CNAMEs
- Provider fingerprints
- Takeover indicators
"Barrion's security scanning has helped us implement best security practices efficiently, saving us countless hours."
Sarah Chen
Head of Security
"We identified and fixed critical vulnerabilities before our platform launch, saving us from potential data breaches."
Marcus Anderson
CTO
"Barrion gives us peace of mind, knowing we're notified of any security issues. Exactly what our team needed."
Oskar Nilsson
Tech Lead
Scan in three simple steps
Fast, safe, non-intrusive checks with actionable results.
Start scan
Enter your URL, and click the start scan button to begin.
Scan runs
Barrion performs passive, read-only security checks with minimal site impact.
View results
See security findings with prioritized, actionable recommendations.
What is subdomain takeover?
When a DNS record points to a deprovisioned resource (like an unused SaaS hostname), attackers can claim it and serve content under your subdomain.
How to prevent takeovers
- Remove stale CNAMEs/ALIAS records
- Use provider verification and auto-cleanup
- Continuously monitor DNS changes
Tool-specific questions
Which providers are commonly abused?
Can wildcard DNS cause issues?
How do I detect stale CNAMEs?
Why Choose Barrion?
Real-Time Results
Instant security analysis with detailed reports, giving you an immediate security overview
Comprehensive Checks
Multiple best-practice security checks in a single scan, for broad coverage
Actionable and Effective
Clear recommendations for fixes, helping you improve your security quickly and effectively
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