INTLPOL 268: Hack Lab
Week 2 · Part 2
Network Security, Part 2
Alex StamosStanford University
Fall 2026Friday, October 2, 2026
Week 2 · Part 2
What will we learn today?
Today, we will…
- What is special for Wi-Fi?
- How to hack Wi-Fi networks
Recap
The Internet is really a network of networks
Part one
Wi-Fi
Wi-Fi · IEEE 802
Wi-Fi is Ethernet
Both are IEEE 802 link-layer standards:
802.3 for the wire, 802.11 for the air
802.1Higher Layer LAN Protocols Working Groupactive
802.2LLCdisbanded
802.3Ethernetactive
802.4Token busdisbanded
802.5Token ring MAC layerdisbanded
802.6MANs (DQDB)disbanded
802.7Broadband LAN using Coaxial Cabledisbanded
802.8Fiber Optic TAGdisbanded
802.9Integrated Services LAN (ISLAN or isoEthernet)disbanded
802.10Interoperable LAN Securitydisbanded
802.11Wireless LAN (WLAN) & Mesh (Wi-Fi certification)active
802.12100BaseVGdisbanded
802.13Unused (reserved for Fast Ethernet development)reserved
802.14Cable modemsdisbanded
802.15Wireless PANactive
802.15.1Bluetooth certificationdisbanded
802.15.2IEEE 802.15 and IEEE 802.11 coexistencehibernating
802.15.3High-Rate wireless PAN (e.g., UWB)—
802.15.4Low-Rate wireless PAN (e.g., ZigBee, WirelessHART, MiWi)active
IEEE Std 802.11ac™-2013 — Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications · Amendment 4: Enhancements for Very High Throughput for Operation in Bands below 6 GHz
Figure 8-449
Zero or oneZero or oneZero or more
Category
Public Action
Channel Switch Mode
New Operating Class
New Channel Number
Channel Switch Count
Mesh Channel Switch Parameters element
New Country element
Wide Bandwidth Channel Switch element
New VHT Transmit Power Envelope element
1111116variablevariablevariable
Octets
Wikipedia contributors. (n.d.). IEEE 802 — Working groups. Wikipedia. en.wikipedia.org/wiki/IEEE_802 · IEEE. (2013). IEEE Std 802.11ac-2013, §8.5.8.7, Figure 8-449. IEEE Computer Society.
Wi-Fi · 802.11
Association
LaptopMAC1
Access pointSSID HomeNet
Hi, I’m SSID HomeNet
I’m MAC1 and want to join!
Sure!
Here is some data
Here is some data
Wi-Fi · 802.11
Hidden SSID
LaptopMAC1
Access pointSSID hidden
*Silence*
I’m MAC1 and want to join SecretNet!
Sure! I’m SecretNet
Here is some data
Here is some data
Part two
What can go wrong?
Wi-Fi · 802.11 · WPA
So we have Wi-Fi Protected Access (WPA)
LaptopMAC1
Access pointSSID HomeNet
Hi, I’m SSID HomeNet and I require WPA
I’m MAC1 and want to join!
Sure! Here is a nonce. Prove you have the password
Here is my part of the encryption key
Here is my part of the key
8@#%$TWR
#$%^4t3466
Live