Introduction to WPA3

4 min readJuly 20, 2020Add comment

Play episode

In this episode, we are providing an introduction to WPA3. We also show how to configure it on a Cisco controller as well as how you could validate it by looking at Wi-Fi frames:

Introduction

WPA3 is the improved version of Wi-Fi security. It updates WPA2 which is commonly used everywhere in Wi-Fi networks.

Why the need for WPA3?

KRACK Attack
https://www.cleartosend.net/cts-094-sealing-krack-attack/
WPA2-PSK is subject to dictionary attacks

WPA3 brings the following:

Increased crypto strength
Dumps legacy protocols
Mandates Protected Management Frames (PMF)
- https://www.cleartosend.net/802-11w-management-frame-protection/
Mandatory for Wi-Fi 6 (more and more devices will support WPA3)

There are two versions of WPA3 which are similarly named from WPA2:

WPA3-Personal
- Pre-shared Key
- Simultaneous Authentication of Equals (SAE) is used
WPA3-Enterprise
- Builds upon WPA2-Enterprise
- Enhanced encryption
- WPA3-Enterprise also offers an optional mode using 192-bit minimum-strength security protocols and cryptographic tools to better protect sensitive data:
  - Authenticated encryption: 256-bit Galois/Counter Mode Protocol (GCMP-256)
  - Key derivation and confirmation: 384-bit Hashed Message Authentication Mode (HMAC) with Secure Hash Algorithm (HMAC-SHA384)
  - Key establishment and authentication: Elliptic Curve Diffie-Hellman (ECDH) exchange and Elliptic Curve Digital Signature Algorithm (ECDSA) using a 384-bit elliptic curve
  - Robust management frame protection: 256-bit Broadcast/Multicast Integrity Protocol Galois Message Authentication Code (BIP-GMAC-256)

WPA3 Modes

There are a few modes WPA3 can be implemented

WPA3-Personal only
WPA3-Personal transition
WPA3-Enterprise only
WPA3-Enterprise transition
WPA3-Enterprise 192-bit
WPA3 Fast BSS Transition
WPA3-Enterprise Server Certificate Validation

WPA3-Personal

Mandatory
- AP enables at least AKM suite selector of 00-0F-AC:8 (SAE Authentication)
- STA allows at least AKM 00-0F-AC:8 for association
- AP and STA must use PMF
  - AP and STA sets MFPC and MFPR to 1
- Must use only DH groups 15-21, group 19
Requirement
- AP and STA does not enable AKM 00-0F-AC:2 (WPA2-PSK) and 00-0F-AC:6 (PSK using SHA-256)
- AP doesn’t enable WPA on same BSS with WPA3-Personal
- No WEP and TKIP on same BSS as WPA3-Personal
- STA will use SAE when AP supports SAE and PSK

WPA3-Personal Transition

Mandatory
- AP enables at least AKM 00-0F-AC:2 (WPA2-PSK) and 00-0F-AC:8 (WPA3-Personal)
- STA allows at least AKM 00-0F-AC:2 (WPA2-PSK) and 00-0F-AC:8
- AP sets MFPC to 1, MFPR to 0
- STA sets MFPC to 1, MFPR to 0
- AP rejects association for SAE if PMF is not negotiated
- STA negotiates PMF when associating to AP using SAE
Recommended
- AP enables AKM 00-0F-AC:6
- STA allows 00-0F-AC:6
Requirement
- AP doesn’t enable WPA on same BSS with WPA3-Personal
- No WEP and TKIP on same BSS as WPA3-Personal
- STA will use SAE when AP supports SAE and PSK

WPA3-Enterprise Only

PMF will be set to capable which is the MFPC bit set to 1 and MFPR bit set to 1 in the RSN Capabilities field
No WPA version 1 enabled on the same BSS on WPA3-Enterprise

WPA3-Enterprise transition mode

WPA2-Enterprise and WPA3-Enterprise transition mode on same BSS, PMF will be set to capable which is the MFPC bit set to 1 and MFPR bit set to 0 in the RSN Capabilities field
WPA3-Enterprise STA will negotiate PMF when using WPA3-Enterprise transition mode
No WPA version 1 enabled on the same BSS on WPA3-Enterprise

WPA3-Enterprise 192-bit

For sensitive environments needing higher security requirements
PMF is required
Permitted EAP cipher suites for use with 192-bit mode:
- TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
  - ECDHE and ECDSA using the 384-bit prime modulus curve P-384
- TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
  - ECDHE using the 384-bit prime modulus curve P-384
  - RSA ≥ 3072-bit modulus
- TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
  - RSA ≥ 3072-bit modulus
  - DHE ≥ 3072-bit modulus

WPA3 Fast BSS Transition

Added to WPA3 Spec on 12/20/2019
Different modes:
- Fast BSS Transition for WPA3-Personal transition mode
- Fast BSS Transition for WPA3-Enterprise transition mode
- Fast BSS Transition for WPA3-Personal only mode
- Fast BSS Transition for WPA3-Enterprise only mode
There is an order of AKM preference
- Personal Modes
  - FT Authentication using SAE 00-0F-AC:9
  - SAE Authentication 00-0F-AC:8
  - FT Authentication using PSK 00-0F-AC:4
  - PSK using SHA-256 00-0F-AC:6
  - PSK 00-0F-AC:2
- Enterprise Modes
  - FT Authentication using 802.1X (SHA 256) 00-0F-AC:3
  - Authentication using 802.1X (SHA 256) 00-0F-AC:5
  - Authentication 802.1X 00-0F-AC:1