In this writeup, I’ll describe a new technique to crack WPA PSK (Pre-Shared Key) passwords.
In order to make use of this new attack you need the following tools:
This attack was discovered accidentally while looking for new ways to attack the new WPA3 security standard. WPA3 will be much harder to attack because of its modern key establishment protocol called “Simultaneous Authentication of Equals” (SAE).
The main difference from existing attacks is that in this attack, capture of a full EAPOL 4-way handshake is not required. The new attack is performed on the RSN IE (Robust Security Network Information Element) of a single EAPOL frame.
At this time, we do not know for which vendors or for how many routers this technique will work, but we think it will work against all 802.11i/p/q/r networks with roaming functions enabled (most modern routers).
The main advantages of this attack are as follow:
- No more regular users required – because the attacker directly communicates with the AP (aka “client-less” attack)
- No more waiting for a complete 4-way handshake between the regular user and the AP
- No more eventual retransmissions of EAPOL frames (which can lead to uncrackable results)
- No more eventual invalid passwords sent by the regular user
- No more lost EAPOL frames when the regular user or the AP is too far away from the attacker
- No more fixing of nonce and replaycounter values required (resulting in slightly higher speeds)
- No more special output format (pcap, hccapx, etc.) – final data will appear as regular hex encoded string