As red team members and even “evil attackers”, we’ve been finding numerous ways to exfiltrate data from networks with inexpensive hardware: Ethernet, WiFi and cellular (2G, 3G and LTE). The first two are highly detectable, while the latter is expensive and both leave a paper trail. We found a way to use a medium that is right under everypony’s nose; low power, broadcast FM radio. With a Raspberry Pi and a length of wire, we can send text and raw binary data with a method nopony (until now) would think to look for. We receive the data with an RTL-SDR, putting our overall hardware budget at $20. In this demo, we will show you how to build and use this system. We’ll share tales of the custom software and transmission protocols. You want to see it in action? We’ve got demos. You want the software? Yep, you can have that too. We’re excited to offer Vapor Trail to you, the first FM radio data exfiltration tool. Sure, HAM radio folks have had digital modes for years, but we’ve done better AND cheaper. We’ve effectively created our own RF digital mode for pwnage, HAM radio data transfer and redundant communication methods. Why? Because we can. We want to go undetected with current capabilities. Turns out, our approach is quite novel for pulling data right from a network via pcaps or tool output.

Watch Vapor Trail demo from Wild West Hacking Fest