00 — Overview

Subdomain Takeover

Claim domains that companies forgot to clean up. Dangling CNAME records pointing to deprovisioned cloud services are everywhere — and they hand you a company subdomain on a plate.

Intermediate·40 min·5 tasks
// By the end of this module
Explain what a dangling CNAME is and why it enables subdomain takeover
Enumerate subdomains passively and actively using subfinder, dnsx, and httpx
Fingerprint unclaimed external services by their error responses
Demonstrate a responsible PoC takeover and document it for a bug report
Implement DNS hygiene practices to prevent takeovers in production
// Prerequisites
Complete these before starting this module for the best experience.