A memory corruption issue was addressed with improved input validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6, watchOS 6.2.8. A remote attacker may be able to cause unexpected system termination or corrupt kernel memory.
https://support.apple.com/kb/HT211291
https://support.apple.com/kb/HT211289
https://support.apple.com/kb/HT211288
http://packetstormsecurity.com/files/162119/iOS-macOS-Radio-Proximity-Kernel-Memory-Corruption.html