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tutorials · lab 03 · dns txt chain reconnaissance
03 / 10 · ML
01step · watch first

DNS is more than the internet's phonebook.

A quick primer: DNS is the system that turns a web name into a machine address — but it can also carry little text notes. This lab teaches you to follow a hidden trail of those notes. Watch through, then jump to the simulation to walk the whole trail from start to finish.

Lesson · DNS TXT Chain Reconnaissance ~5 min
Summary what to remember
  • 1DNS is the internet's phonebook. It turns names into addresses — but you can also pin little text notes to a name, and the whole internet trusts them.
  • 2One command asks the question. dig +short TXT name reads the notes on a name, one per line, with no clutter.
  • 3Scrambled text hides nothing. An ending of == and a jumble of letters and numbers means it's base64 — and base64 -d unscrambles it into the next place to look.
  • 4Check before you follow. Fake notes sit right next to the real ones — only trust the note that starts with next=.
  • 5The last note is the prize. dig +short TXT stageN.acme.test hands back the flag itself at the end of the trail.
beginner 150 xp ~20 min track · ML
? Quick check · before you continue 1 question · pick one

QYou've found a note on acme.test that reads next=c3RhZ2UyLmFjbWUudGVzdA==. What's your move?