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DNS Enumeration
DNS Enumeration DNS enumeration gathers a domain’s records and tries a zone transfer (AXFR), which would dump every hostname. If AXFR is allowed, one command leaks the whole internal map. Fix: allow AXFR only to secondary DNS servers (with TSIG), and use split DNS. Getting upset when AXFR fails . A
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What this card says
What it is
DNS enumeration gathers a domain’s records and tries a zone transfer (AXFR), which would dump every hostname.
Why it matters for security
If AXFR is allowed, one command leaks the whole internal map.
Fix: allow AXFR only to secondary DNS servers (with TSIG), and use split DNS.
Common mistake
Getting upset when AXFR fails. A failure means the server is hardened.
In an interview, “AXFR refused” is a positive finding for the defender.
Learn more in the lesson: 37.7 DNS Enumeration