How WiFi Security Works (and Breaks)

Free lesson 1 of 7 from WiFi & Wireless Hacking — How WPA2 falls: capture, the clientless PMKID attack, and offline cracking — hands-on.. No account, no card.

The password never travels — so how do we crack it?

WPA2-PSK never sends your WiFi password over the air. Instead the AP and client prove they both know it via a math handshake. An attacker captures that proof and then guesses passwords offline against it — no interaction with the network, unlimited attempts. Weak passphrase = cracked.

The modern twist: the PMKID attack needs no client at all — a single frame from the AP is enough. That's what you'll crack in the lab (no radio required — we captured one for you).

🎯 Your kit

cat ~/wifi/README.txt
ls -la ~/wifi/     # handshake.22000 · wordlist.txt · flag.enc
🎯 Challenge: Read the range README. What does the PMKID attack let you skip that the classic 4-way-handshake capture requires?
Show solution

Classic capture needs a client connecting (to grab the 4-way handshake, sometimes forced with a deauth). PMKID is clientless — you get it straight from the AP's first response, so you don't need to wait for or kick any user.

⚖️ Only attack networks you own or are authorized to test. Cracking others' WiFi is illegal.

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