The client 802.11 mac implementation in Espressif ESP8266_NONOS_SDK 2.2.0 through 3.1.0 does not validate correctly the RSN AuthKey suite list count in beacon frames, probe responses, and association responses, which allows attackers in radio range to cause a denial of service (crash) via a crafted message.
https://matheus-garbelini.github.io/home/post/esp8266-beacon-frame-crash/