A NOW-PATCHED BUG made it possible for hackers to dump malicious APK files on nearby Android devices without any kind of security warning from Oreo onwards.
Android Beam was the culprit. For those unfamiliar with Beam, it’s a way of transferring files, pictures and videos between two Android devices using NFC rather than WiFi, Bluetooth or a tedious process involving cables and a laptop.
The fact that you can send APK files over Beam in itself isn’t a problem.