The 802.11 beacon handling routine failed to validate the length of an IEEE 802.11s Mesh ID before copying it to a heap-allocated buffer. While a FreeBSD Wi-Fi client is in scanning mode (i.e., not associated with a SSID) a malicious beacon frame may overwrite kernel memory, leading to remote code execution.
https://security.freebsd.org/advisories/FreeBSD-SA-22:07.wifi_meshid.asc