Researchers Steal Door Badge Credentials Using Smartphone Bluetooth

Next week at Black Hat USA a pair of researchers will be demonstrating a new tool they developed that can easily be placed on just about any commercial door reader device to siphon away key card credential information and send it via Bluetooth to a smartphone so that an attacker could easily clone cards and circumvent facility security measures.

Developed by Eric Evenchick, embedded systems architect of Faraday Future, and Mark Baseggio, managing principal consultant of Accuvant and FishNet Security (soon to be Optiv Security), the tool takes advantage of weaknesses in the underlying Wiegand door controller protocol that electronic access control systems today still depend upon -- despite the fact that the protocol was developed in the Apollo 11 era, says Evenchick.

"It has no security, it's just total clear text electrical signaling that we can exploit," he explains. "We take a cheap piece of hardware with Bluetooth, stick it on (the wall reader's) wires, and we're able to gain control of an access control system. Anyone walking up to the building will still be able to badge in and get into the door, it'll beep, everything's normal. The only difference is, that device is now collecting all of those numbers that identify people."

Using the wireless connection, the device then broadcasts out to a mobile device of the attacker's choice, even sending out push notifications when data is collected.

"The phone will vibrate as you're walking around to let you know," Baseggio says.

While many of these wall units come with a special switch for anti-tampering purposes, most implementations of them don't hook the switch up, and in many cases companies "don't even bother putting the lines in the walls necessary to hook them up," which Baseggio says is an obvious first step for mitigating risk. Additionally, the two presenter recommend companies pay better attention to the console running these units looking for alarms and even doing heuristics on login data to look for anomalies in how certain employees are badging in. Finally, video cameras posted at all badge readers can also help correlate video recordings to access logs to ensure the person the system says entered the door really was that individual.

Baseggio first came up with the idea of the project as part of his work as a penetration tester for Accuvant. Since he and Evenchick developed the tool, he's managed to surprise a lot of customers about how insecure their facilities really are.

"I was going to all of these client sites... in Asia, in Europe, in North America, and whether [the company was] a bank or a manufacturing facility, it seemed like all the clients were kind of shocked when I actually showed them how easy it was to abuse these systems," he says. "Me being able to pull my phone out of a pocket and unlock a door that's only designed to work with a card that they had provisioned themselves is quite impactful."

The hardware specifications for the tool and the software to run it, as well as the software for mobile devices will all be made available on Github following the pair's presentation.  In addition, Accuvant and FishNet will be giving away 200 already-made devices to audience members vetted as professional penetration testers.