Broadcom BCM43xx Wi-Fi chips allow remote attackers to execute arbitrary code via unspecified vectors, aka the "Broadpwn" issue.
https://support.apple.com/kb/HT210121
https://source.android.com/security/bulletin/2017-07-01
https://seclists.org/bugtraq/2019/May/30
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-9417
https://lists.debian.org/debian-lts-announce/2018/11/msg00015.html
http://www.securitytracker.com/id/1039330
http://www.securitytracker.com/id/1038950