The RSN IE is a optional field that contains the Pairwise Master Key Identifier (PMKID) generated by a router when a user tries to authenticate. This method works by extracting the RSN IE (Robust Security Network Information Element) from a single EAPOL frame.
According to Steube, this method will work against almost all routers utilizing 802.11i/p/q/r networks with roaming enabled. This new method was discovered by Jens 'atom' Steube, the developer of the popular Hashcat password cracking tool, when looking for new ways to crack the WPA3 wireless security protocol. While previous WPA/WPA2 cracking methods required an attacker to wait for a user to login to a wireless network and capture a full authentication handshake, this new method only requires a single frame which the attacker can request from the AP because it is a regular part of the protocol.
A new technique has been discovered to easily retrieve the Pairwise Master Key Identifier (PMKID) from a router using WPA/WPA2 security, which can then be used to crack the wireless password of the router.