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How does the 4 way handshake in WPA work?
TEK is used for encrypting traffic between client and AP, later during session. Now the WPA 4-way handshake: AP sends ANonse (AP Nonce) to client, which is basically a random Integer of 256 bits. Client use the ANonce and PMK to generate PTK (Pairwise Transient Key), and send CNonce (Client Nonce) and MAC.
How to generate Mic in 4 way handshake?
3) M3 Message: Now lets generate the MIC for the M3 Message in the 4-way Handshake. In this Message Install bit will be set to 1 in key information, so that Client will install the PTK. And generated keys will be used to encrypt the unicast/broadcast traffic. Observe the below M3 Message and we will calculate the MIC for the M3 Packet.
Is the mic generation the same for WPA2 and WPA3?
MIC Generation will be same for WPA2-PMF, WPA3 and OWE because they all use same MIC generation AES-CMAC. If we know the KCK for the 4-way handshake exchange then the procedure will be the same for all of them. How easy is it Know the PTK ? It will be easy to get the PTK when we are using WPA2 and WPA2-PMF.
How is the PMK used in a handshake?
The PMK isn’t even sent during the handshake, instead it is used to calculate a Message Integrity Check (MIC). You basically need to perform a dictionary or bruteforce attack on the handshake until you find a password which results in the same MIC as in the packets.
How does WPA2 work in a home network?
From my understanding this is how WPA2 works for home networks: PSK (Pre-Shared Key) is used to generate PMK (Pairwise Master Key), which is used together with ANonce (AP Nonce) to create PTK (Pairwise Transient Key).
Is there a security flaw in WPA2 encryption?
Standard WPA2-PSK encryption is supposed to prevent this from happening — but it’s not as foolproof as you might think. This isn’t huge breaking news about a new security flaw. Rather, this is the way WPA2-PSK has always been implemented. But it’s something most people don’t know.
Is there a weakness in WPA2-PSK network?
This is kind of true — but there’s a big weakness here. The problem with WPA2-PSK is that it uses a “Pre-Shared Key.” This key is the password, or passphrase, you have to enter to connect to the Wi-Fi network. Everyone that connects uses the same passphrase. It’s quite easy for someone to monitor this encrypted traffic.
Which is the shared key in WPA2 PSK?
The earlier EAP exchange or WPA2-PSK has provided the shared secret key PMK (Pairwise Master Key). This key is, however, designed to last the entire session and should be exposed as little as possible. Therefore the four-way handshake is used to establish another key called the PTK (Pairwise Transient Key).
How does the 4-way handshake cracking work?
KCK is used to construct MAC in EAPOL packets 2,3 and 4. KEK is used to encrypt some data sent to client (for example GTK). TEK is used for encrypting traffic between client and AP, later during session. Now the WPA 4-way handshake: AP sends ANonse (AP Nonce) to client, which is basically a random Integer of 256 bits.
How does the WPA key confirmation key work?
The PTK is derived from the PMK, two nonces, the MAC addresses of both the client and the authenticator. This 64 bytes PTK is split into: 16 bytes Key Confirmation Key (KCK). Used to compute MIC for integrity 16 bytes Key Encryption Key (KEK).