The default configuration of Widcomm Bluetooth for Windows (BTW) 4.0.1.1500 and earlier, as installed on Belkin Bluetooth Software 1.4.2 Build 10 and ANYCOM Blue USB-130-250 Software 4.0.1.1500, and possibly other devices, sets null Authentication and Authorization values, which allows remote attackers to send arbitrary audio and possibly eavesdrop using the microphone via the Hands Free Audio Gateway and Headset profile.