An issue was discovered on COROS PACE 3 devices through 3.0808.0

An issue was discovered on COROS PACE 3 devices through 3.0808.0. It starts advertising if no device is connected via Bluetooth. This allows an attacker to connect with the device via BLE if no other device is connected. While connected, none of the BLE services and characteristics of the device require any authentication or security level. Therefore, any characteristic, depending on their mode of operation (read/write/notify), can be used by the connected attacker. This allows, for example, configuring the device, sending notifications, resetting the device to factory settings, or installing software.