Free Subdomain Discovery Tool
Free subdomain discovery tool — find subdomains for any domain using Certificate Transparency logs. Passive reconnaissance with no direct scanning required.
What Are Certificate Transparency Logs?
Certificate Transparency (CT) is a framework for monitoring and auditing SSL/TLS certificates. All major CAs are required to log certificates they issue to public CT logs.
Security researchers and domain owners use CT logs to detect unauthorized certificates, discover forgotten subdomains, and map an organization's web infrastructure.
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