WiFi Insecurity

WEP

Don't use this!!

src: http://www.cs.sjsu.edu/~stamp/CS265/projects/Spr05/papers/WEP.pdf

The Core Problem is IV is used incorrectly

Key Reuse with RC4

WPA

Wi-Fi Protected Access

WPA Modes

• WPA-Personal: Static pre-shared key (aka. password). Most common in homes and coffee shops.
• WPA-Enterprise: Requires and authentication server, has lots of modes.
• WPS: Wi-Fi Protected Setup. Uses and 8-digit PIN. Broken, disable if you can.

WPA's Keys

• PMK: Pairwise Master Key, derived from the password (WPA-Personal) or the EAP parameters.
• PTK: Pairwise Transient Key, PMK || ANonce || SNonce || AP MAC || Station MAC, used to encrypt traffic
• GTK: Group Temporal Key, used to encrypt/decrypt broadcast traffic. Generated by the AP

The WPA Handshake

1. The AP sends a nonce ANonce and a Key Replay Counter to the station.
2. The station constructs the PTK. The station sends a nonce SNonce, a MIC and the Key Replay Counter to the AP.
3. The AP verifies message 2 and then sends the GTK and another MIC to the station.
4. The station verifies the AP's message and sends a confirmation

WPA 3

The Future!

Thank you Mathy Vanhoef

More Secure Handshake

Eliminates offline dictionary attacks and provides forward secrecy using SAE

Replace WPS

A little complicated, but is based on the devices wanting to connect providing a public key to the router

Unauthenticated Encryption

Not sure how this will work, but Opportunistic Wireless Encryption (OWE) is a strong candidate