Cracking A Bluetooth Credit Card

April 8, 2018 by Tom Nardi 44 Comments

You might be surprised to find out that it’s actually not a good idea to put all of your credit card information on a little Bluetooth enabled device in your pocket. Oh, what’s that? You knew already? Well in that case you won’t find the following information terribly shocking, but it’s still a fascinating look at how security researchers systematically break down a device in an effort to find the chinks in its armor.

[Mike Ryan] of ICE9 Consulting has recently published an article detailing the work done to examine and ultimately defeat the security on the FUZE Card. From using an x-ray machine to do non-destructive reconnaissance on the device’s internals to methodically discovering all the commands it responds to over Bluetooth, it’s safe to say the FUZE Card is cracked wide open at this point.

To be clear, the attacker must still pair with FUZE, so physical access is required. But as pointed out by [Mike] in the blog post, handing your card over to a merchant is standard operating procedure in many cases. It isn’t as if it would be hard to get a hold of one of these FUZE cards for a minute or two without the owner becoming suspicious. Pairing FUZE to the Linux device to continue to the next step of the attack only takes a few seconds, as demonstrated in the video after the break.

Once paired, the attacker can simply send a BLE command to FUZE which disables the lock screen. It’s really that simple. The attacker can also send commands to dump credit card info over Bluetooth, meaning they could download your information even when the card is “safely” back in your pocket. The inherent failure in the FUZE design is that you don’t need to provide any sort of authentication to pair it to a new Bluetooth device. It makes the (very dangerous) assumption that the person holding it is entitled to do so.

Even if you know better than to ever buy a device like this, the post [Mike] has written up is really a must-read for anyone who’s ever looked at a device and tried to figure out what was going on in its little silicon brain. We especially liked his assertion that reverse engineering a device essentially boils down to: “staring, thinking, a little experimentation, but mostly staring and thinking.” We’re having an internal debate here at Hackaday HQ about making that the site’s tagline.

Incidentally, this is very similar to the Bluetooth gun “safe” that was cracked not so long ago. At this point, it might be wise to just stay away from anything with that little blue logo on it if you intend to trust it with your identity and/or deadly weapon.

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Monitor Foot Traffic Using Radio

April 6, 2018 by Bryan Cockfield 15 Comments

We talk a lot about information security around here, but in reality it’s not at the forefront of everyone’s minds. Most people are content to walk around with their phones constantly looking for WiFi or Bluetooth connections despite the dangers. But if you’re not a black hat sort of person, you can do something like [Verkehrsrot] did and use all of these phones to do something useful and harmless.

[Verkehrsrot]’s project involves building a radio listening device in order to get an estimate of the amount of traffic in a particular area. The device polls for and detects WiFi and Bluetooth devices nearby and tallies them. For the privacy-minded, it doesn’t persistently store any information about the people or the devices that it detects. The project also runs on a variety of platforms, although you can get the whole thing up and running with little more than an ESP32 and a small lithium-ion battery.

If you’re looking for a useful way to tally the number of people in a given area, this project could be the thing for you. Not everyone keeps their WiFi and Bluetooth turned on, but even so this is still a good way to estimate. But if you need to count everyone going into a room, for example, you’ll need another way to count them.

Cracking An Encrypted External Hard Drive

March 16, 2018 by Tom Nardi 13 Comments

As far as hobbies go, auditing high security external hard drives is not terribly popular. But it’s what [Raphaël Rigo] is into, and truth be told, we’re glad it’s how he gets his kicks. Not only does it make for fascinating content for us to salivate over, but it’s nice to know there’s somebody with his particular skill set out there keeping an eye out for dodgy hardware.

No word on how the “Secret Wang” performs

The latest device to catch his watchful eye is the Aigo “Patriot” SK8671. In a series of posts on his blog, [Raphaël] tears down the drive and proceeds to launch several attacks against it until he finally stumbles upon the trick to dump the user’s encryption PIN. It’s not exactly easy, it did take him about a week of work to sort it all out, but it’s bad enough that you should probably take this particular item off the wishlist on your favorite overseas importer.

[Raphaël] treats us to a proper teardown, including gratuitous images of chips under the microscope. He’s able to identify a number of components on the board, including a PM25LD010 SPI flash chip, Jmicron JMS539 USB-SATA controller, and Cypress CY8C21434 microcontroller. By hooking his logic analyzer up to the SPI chip he was able to dump its contents, but didn’t find anything that seemed particularly useful.

The second post in the series has all the gory details on how he eventually gained access to the CY8C21434 microcontroller, including a description of the methods which didn’t work (something we always love to see). [Raphaël] goes into great detail about the attack that eventually busted the device open: “cold boot stepping”. This method allowed him to painstakingly copy the contents of the chip’s flash; pulling 8192 bytes from the microcontroller took approximately 48 hours. By comparing flash dumps he was able to eventually discover where the PIN was being stored, and as an added bonus, found it was in plaintext. A bit of Python later, and he had a tool to pull the PIN from the drive’s chip.

This isn’t the first time we’ve seen a “secure” hard drive that ended up being anything but. We’ve even been witness to a safe being opened over Bluetooth. Seems like this whole “Security by Obscurity” thing might not be such a hot idea after all…

Color-Coded Key Opens Doors, Opportunities

March 9, 2018 by Bryan Cockfield 20 Comments

Of all the ways to open up a lock, there are some tried and true methods. Keys, combinations, RFIDs, picks, and explosives have all had their time and place, but now someone else wants to try something new. [Erik] has come up with a lock that opens when it is shown a pattern of colors.

The lock in question uses a set of color coded cards as the “keys”. When the cards are inserted in the lock, a TCS230 color sensor interprets the pattern on the cards and sends the information over to an Arduino Uno. From there, the Arduino can command the physical lock to open if the pattern is a match, although [Erik] is still waiting on the locking mechanism to arrive while he continues to prototype the device.

This is a fairly unique idea with a number of upsides. First, the code can’t be “stolen” from inside a wallet like RFID cards can. (Although if you can take a picture of the card all bets are off.) If you lose your key, you can simply print another one, and the device is able to handle multiple different keys and log the usage of each one. Additionally, no specialized equipment is needed to create the cards, unlike technologies that rely on magnetic strips. Of course, there’s always this classic way of opening doors if you’d rather go old school with your home locks.

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Memcached Servers Abused For DDoS Attacks

March 1, 2018 by Bob Baddeley 11 Comments

Cloudflare announced recently that they are seeing an increase in amplification attacks using memcached servers, and that this exploit has the potential to be a big problem because memcached is capable of amplifying an attack significantly. This takes DDoS attacks to a new level, but the good news is that the problem is confined to a few thousand misconfigured servers, and the solution is to put the servers behind a tighter firewall and to disable UDP. What’s interesting is how the fundamental workings of the Internet are exploited to create and direct a massive amount of traffic.

We start with a botnet. This is when a bunch of Internet-connected devices are compromised and controlled by a malicious user. This could be a set of specific brand of web camera or printer or computer with unsecured firmware. Once the device is compromised, the malicious user can control the botnet and have it execute code. This code could mine cryptocurrency, upload sensitive data, or create a lot of web traffic directed at a particular server, flooding it with requests and creating a distributed denial of service (DDoS) attack that takes down the server. Since the server can’t distinguish regular traffic from malicious traffic, it can’t filter it out and becomes unresponsive.

This DDoS attack is limited to the size of the botnet’s bandwidth, though. If all the web cameras in the botnet are pounding a server as fast as they can, the botnet has reached its max. The next trick is called an amplification attack, and it exploits UDP. UDP (as opposed to TCP) is like the early post office; you send mail and hope it gets there, and if it doesn’t then oh well. There’s no handshaking between communicating computers. When a device sends a UDP packet to a server, it includes the return address so that the server can send the response back. If the device sends a carefully crafted fake request with a different return address, then the server will send the response to that spoofed return address.

So if the web camera sends a request to Server A and the response is sent to Server B, then Server A is unintentionally attacking Server B. If the request is the same size as the response, then there’s no benefit to this attack. If the request is smaller than the response, and Server A sends Server B a bunch of unrequested data for every request from the camera, then you have a successful amplification attack. In the case of memcached, traffic can be amplified by more than 50,000 times, meaning that a small botnet can have a huge effect.

Memcached is a memory caching system whose primary use is to help large websites by caching data that would otherwise be stored in a database or API, so it really shouldn’t be publicly accessible anyway. And the solution is to turn off public-facing memcached over UDP, but the larger solution is to think about what things you are making available to the Internet, and how they can be used maliciously.

France Proposes Software Security Liability For Manufacturers, Open Source As Support Ends

February 22, 2018 by Jenny List 58 Comments

It sometimes seems as though barely a week can go by without yet another major software-related hardware vulnerability story. As manufacturers grapple with the demands of no longer building simple appliances but instead supplying them containing software that may expose itself to the world over the Internet, we see devices shipped with insecure firmware and little care for its support or updating after the sale.

The French government have a proposal to address this problem that may be of interest to our community, to make manufacturers liable for the security of a product while it is on the market, and with the possibility of requiring its software to be made open-source at end-of-life. In the first instance it can only be a good thing for device security to be put at the top of a manufacturer’s agenda, and in the second the ready availability of source code would present reverse engineers with a bonanza.

It’s worth making the point that this is a strategy document, what it contains are only proposals and not laws. As a 166 page French-language PDF it’s a long read for any Francophones among you and contains many other aspects of the French take on cybersecurity. But it’s important, because it shows the likely direction that France intends to take on this issue within the EU. At an EU level this could then represent a globally significant move that would affect products sold far and wide.

What do we expect to happen in reality though? It would be nice to think that security holes in consumer devices would be neutralised overnight and then we’d have source code for a load of devices, but we’d reluctantly have to say we’ll believe it when we see it. It is more likely that manufacturers will fight it tooth and nail, and given some recent stories about devices being bricked by software updates at the end of support we could even see many of them willingly consigning their products to the e-waste bins rather than complying. We’d love to be proven wrong, but perhaps we’re too used to such stories. Either way this will be an interesting story to watch, and we’ll keep you posted.

Merci beaucoup [Sebastien] for the invaluable French-language help.

French flag: Wox-globe-trotter [Public domain].

Cell Phone Surveillance Car

January 30, 2018 by James Hobson 15 Comments

There are many viable options for home security systems, but where is the fun in watching a static camera feed from inside your place? The freedom to really look around might have been what compelled [Varun Kumar] to build a security car robot to drive around his place and make sure all is in order.

Aimed at cost-effectiveness and WiFi or internet accessibility, an Android smartphone provides the foundation of this build — skipping the need for a separate Bluetooth or WiFi module — and backed up by an Arduino Uno, an L298 motor controller, and two geared DC motors powering the wheels.

Further taking advantage of the phone’s functionality, the robot is controlled by DTMF tones. Using the app DTMF Tone Generator and outputting through the 3.5mm jack, commands are interpreted by a MT8870DE DTMF decoder module.While this control method carries some risks — as with many IoT-like devices — [Kumar] has circumvented one of DTMF’s vulnerabilities by adding a PIN before the security car will accept any commands.

He obtains a live video feed from the phone using AirDroid in concert with VNC server, and assisted by a servo motor for the phone is enabled to sweep left and right for a better look. A VNC client on [Kumar]’s laptop is able to access the video feed and issue commands. Check it out in action after the break!

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