Source: #_shellntel Blog – SynerComm Author: Dylan Reuter URL: https://www.synercomm.com/executing-shellcode-via-bluetooth-device-authentication/

ONE SENTENCE SUMMARY:

A Bluetooth shellcode loader executes shellcode on a victim machine by triggering device authentication without user interaction.

MAIN POINTS:

1. Shellcode loaders deliver and execute code to establish command and control on victim machines.
2. Memory allocation, decryption, and execution are critical steps in shellcode loading.
3. EDR heavily scrutinizes APIs used for executing shellcode, raising detection risks.
4. Bluetooth authentication can trigger shellcode execution without user approval or notifications.
5. The method relies on nearby discoverable Bluetooth devices for successful execution.
6. Anti-emulation measures prevent execution in sandbox environments lacking Bluetooth hardware.
7. BluetoothFindFirstRadio and BluetoothFindFirstDevice are crucial for discovering Bluetooth hardware and devices.
8. The callback function registers the shellcode execution during Bluetooth device authentication.
9. The technique is suitable for social engineering but requires nearby Bluetooth devices.
10. Source code for the shellcode loader is available on GitHub for further exploration.

TAKEAWAYS:

1. Bluetooth device authentication can be exploited for executing shellcode covertly.
2. EDR detection risks can be mitigated using alternative execution methods.
3. Discoverable Bluetooth devices are essential for this attack to succeed.
4. Understanding Bluetooth APIs is critical for developing similar offensive techniques.
5. Social engineering plays a significant role in delivering the initial payload.