Attack on WiFi without clients ( PMKID attack )
There are a large number of various attacks on WiFi . The most universal attack (working against virtually all access points) is an attack on WPA/WPA2 technology, since it is used in the vast majority of wireless access points. WPA/WPA2, when clients connect to an access point, use the EAPOL security protocol, during which there is a gradual exchange of data between the access point and the client that wants to connect. The essence of the attack lies in the fact that it is necessary to intercept the entire (or at least a part) of the transmitted data and use the search method to find a suitable password. Simply put, you first need to grab a handshake (at the EAPOL stage), and then use brute-force to find the correct password.

At each of these two stages, difficulties may arise: problems with the seizure of a handshake can be caused by many reasons, the most fatal of them being the lack of clients. That is if there are no connecting clients, then the EAPOL protocol is not used, which means there is nothing to intercept.
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