Hackaday Links: July 12, 2020

Based in the US as Hackaday is, it’s easy to overload the news with stories from home. That’s particularly true with dark tales of the expanding surveillance state, which seem to just get worse here on a daily basis. So we’re not exactly sure how we feel to share not one but two international stories of a dystopian bent; one the one hand, pleased that it’s not us for a change, but on the other, sad to see the trend toward less freedom and more monitoring spreading.

The first story comes from Mexico, where apparently everything our community does will soon be illegal. We couch that statement because the analysis is based on Google translations of reports from Mexico, possibly masking the linguistic nuances that undergird legislative prose. So we did some digging and it indeed appears that the Mexican Senate approved a package of reforms to existing federal copyright laws that will make it illegal to do things like installing a non-OEM operating system on a PC, or to use non-branded ink cartridges in a printer. Reverse engineering ROMs will be right out too, making any meaningful security research illegal. There appear to be exceptions to the law, but those are mostly to the benefit of the Mexican government for “national security purposes.” It’ll be a sad day indeed for Mexican hackers if this law is passed.

The other story comes from Germany, where a proposed law would grant sweeping surveillance powers to 19 state intelligence bodies. The law would require ISPs to install hardware in their data centers that would allow law enforcement to receive data and potentially modify it before sending it on to where it was supposed to go. So German Internet users can look forward to state-sponsored man-in-the-middle attacks and trojan injections if this thing passes.

OK, time for a palate cleanser: take an hour to watch a time-lapse of the last decade of activity of our star. NASA put the film together from data sent back by the Solar Dynamics Observatory, a satellite that has been keeping an eye on the Sun from geosynchronous orbit since 2010. Each frame of the film is one hour of solar activity, which may sound like it would be boring to watch, but it’s actually quite interesting and very relaxing. There are exciting moments, too, like enormous solar eruptions and the beautiful but somehow terrifying lunar transits. More terrifying still is a massive coronal mass ejection (CME) captured in June 2011. A more subtle but fascinating phenomenon is the gradual decrease in the number of sunspots over the decade as the Sun goes through its normal eleven-year cycle.

You’ll recall that as a public service to our more gear-headed readers that we recently covered the recall of automotive jack stands sold at Harbor Freight, purveyor of discount tools in the USA. Parts for the jack stands in question had been cast with a degraded mold, making the pawls liable to kick out under load and drop the vehicle, with potentially catastrophic results for anyone working beneath. To their credit, Harbor Freight responded immediately and replaced tons of stands with a new version. But now, Harbor Freight is forced to recall the replacement stands as well, due to a welding error. It’s an embarrassment, to be sure, but to make it as right as possible, Harbor Freight is now accepting any of their brand jack stands for refund or store credit.

And finally, if you thought that the experience of buying a new car couldn’t be any more miserable, wait till you have to pay to use the windshield wipers. Exaggeration? Perhaps only slightly, now that BMW “is planning to move some features of its new cars to a subscription model.” Plans like that are common enough as cars get increasingly complex infotainment systems, or with vehicles like Teslas which can be upgraded remotely. But BMW is actually planning on making options such as heated seats and adaptive cruise control available only by subscription — try it out for a month and if you like it, pay to keep them on for a year. It would aggravate us to no end knowing that the hardware supporting these features had already been installed and were just being held ransom by software. Sounds like a perfect job for a hacker — just not one in Mexico.

Samy Kamkar: Reverse Engineering For A Secure Future

Show of hands: how many of you have parked your car in the driveway, walked up to your house, and pressed your car’s key fob button thinking it would open the front door? We’ve probably all done it and felt a little dopey as a result, but when you think about it, it would be tremendously convenient, especially with grocery bags dangling off each arm and the mail clenched between your teeth. After all, we’re living in the future —  shouldn’t your house be smart enough to know when you’re home?

Reverse engineer par excellence Samy Kamkar might think so, but given his recent experiences with cars smart enough to know when you’re standing outside them, he’d probably have some reservations. Samy dropped by the 2017 Hackaday Superconference in November to discuss the finer points of exploiting security flaws in passive car entry systems, and also sat down with our own Elliot Williams after his talk for a one-on-one interview. Samy has some interesting insights on vehicle cybersecurity, but the practical knowledge he’s gained while exploring the limits of these systems teach some powerful lessons about being a real-world reverse engineer.

Continue reading “Samy Kamkar: Reverse Engineering For A Secure Future”

How To Make Amazon Echo Control Fake WeMo Devices

[Chris] has been playing with the Amazon Echo. It’s sort of like having Siri or Google Now available as part of your home, but with built-in support for certain other home automation appliances like those from Belkin WeMo and Philips. The problem was [Chris] didn’t want to be limited to only those brands. He had other home automation gear that he felt should work with Amazon Echo, but didn’t. That’s when he came up with the clever idea to just emulate one of the supported platforms.

The WeMo devices use UPnP to perform certain functions over the network. [Chris] wanted to see how these communications actually worked, so he fired up his laptop and put his WiFi adapter into monitor mode. Then he used Wireshark to start collecting packets. He found that the device detection function starts out with the Echo searching for WeMo devices using UPnP. The device then responds to the Echo with the device’s URL using HTTP over UDP. The Echo then requests the device’s description using that HTTP URL. The description is then returned as an HTTP response.

The actual “on/off” functionality of the WeMo devices is simpler since the Echo already knows about the device. The Echo simply connects to the WeMo over the HTTP interface and issues a “SetBinaryState” command. The WeMo then obliges and returns a confirmation via HTTP.

WeMo Echo
How Echo Communicates with WeMo Devices

[Steve] was able to use this information to set up his own WeMo “virtual cloud”. Each virtual device would have its own IP address. They would also need to have a listener for UDP broadcasts as well as an HTTP listener running on the WeMo port 49153. Each virtual device would also need to be able to respond to the UPnP discovery requests and the “on/off” commands.

[Chris] used a Linux server, creating a new virtual Ethernet interface for each virtual WeMo switch. A single Python script runs the WeMo emulation, listening for the UPnP broadcast and sending a different response for each virtual device. Part of the response includes the device’s “friendly name”, which is what the Echo listens for when the user says voice commands. Since the virtual WeMo devices are free, this allows [Chris] to make multiple phrases for each device. So rather than be limited to “television”, he can also make a separate device for “TV” that performs the same function. [Chris] is also no longer limited to only specific brands of home automation gear.

There’s still a long way to go in hacking this device. There’s a lot of hardware under the hood to work with. Has anyone else gotten their hands (and bench tools) on one of these?

Stumbling Upon An Uber Vulnerability

[Nathan] is a mobile application developer. He was recently debugging one of his new applications when he stumbled into an interesting security vulnerability while running a program called Charles. Charles is a web proxy that allows you to monitor and analyze the web traffic between your computer and the Internet. The program essentially acts as a man in the middle, allowing you to view all of the request and response data and usually giving you the ability to manipulate it.

While debugging his app, [Nathan] realized he was going to need a ride soon. After opening up the Uber app, he it occurred to him that he was still inspecting this traffic. He decided to poke around and see if he could find anything interesting. Communication from the Uber app to the Uber data center is done via HTTPS. This means that it’s encrypted to protect your information. However, if you are trying to inspect your own traffic you can use Charles to sign your own SSL certificate and decrypt all the information. That’s exactly what [Nathan] did. He doesn’t mention it in his blog post, but we have to wonder if the Uber app warned him of the invalid SSL certificate. If not, this could pose a privacy issue for other users if someone were to perform a man in the middle attack on an unsuspecting victim.

[Nathan] poked around the various requests until he saw something intriguing. There was one repeated request that is used by Uber to “receive and communicate rider location, driver availability, application configurations settings and more”. He noticed that within this request, there is a variable called “isAdmin” and it was set to false. [Nathan] used Charles to intercept this request and change the value to true. He wasn’t sure that it would do anything, but sure enough this unlocked some new features normally only accessible to Uber employees. We’re not exactly sure what these features are good for, but obviously they aren’t meant to be used by just anybody.

Lenovo Shipped PC’s With Spyware That Breaks HTTPS

If you’ve ever purchased a new computer then you are probably familiar with the barrage of bloatware that comes pre-installed. Usually there are system tools, antivirus software trials, and a whole bunch of other things that most of us never wanted in the first place. Well now we can add Superfish spyware to the list.

You may wonder what makes this case so special. A lot of PC’s come with software pre-installed that collect usage statistics for the manufacturer. Superfish is a somewhat extreme case of this. The software actually installs a self-signed root HTTPS certificate. Then, the software uses its own certificates for every single HTTPS session the user opens. If you visit your online banking portal for example, you won’t actually get the certificate from your bank. Instead, you’ll receive a certificate signed by Superfish. Your PC will trust it, because it already has the root certificate installed. This is essentially a man in the middle attack performed by software installed by Lenovo. Superfish uses this ability to do things to your encrypted connection including collecting data, and injecting ads.

As if that wasn’t bad enough, their certificate is actually using a deprecated SHA-1 certificate that uses 1024-bit RSA encryption. This level of encryption is weak and susceptible to attack. In fact, it was reported that [Rob Graham], CEO of Errata Security has already cracked the certificate and revealed the private key. With the private key known to the public, an attacker can easily spoof any HTTPS certificate and systems that are infected with Superfish will just trust it. The user will have no idea that they are visiting a fake phishing website.

Since this discovery was made, Lenovo has released a statement saying that Superfish was installed on some systems that shipped between September and December of 2014. They claim that server-side interactions have been disabled since January, which disables Superfish. They have no plans to pre-load Superfish on any new systems.

Deleting Facebook Albums Without Permission

[Laxman] was poking around Facebook looking for security vulnerabilities. Facebook runs a bug bounty program which means if you can find a vulnerability that’s serious enough, it can earn you cold hard cash. It didn’t take much for [Laxman] to find one worthy of a bounty.

The graph API is the primary way for Facebook apps to read and write to the Facebook social graph. Many apps use this API, but there are limitations to what it can do. For example, the API is unable to delete users’ photo albums. At least, it’s not supposed to be able too. [Laxman] decided to test this claim himself.

He started by sending a command to delete one of his own albums using a graph explorer access token. His request was denied. The application didn’t have the correct permissions to be able to perform that action. It seemed that Facebook was correct and the API was unable to delete photos. [Laxman] had another trick up his sleeve, though. He noticed that the wording of the response suggested that other apps would have the ability to delete the albums, so he decided to check the Facebook mobile application.

He decided to send the same request with a different token. This time he used a token from the Facebook for Mobile application. This actually worked, and resulted in his photo album being deleted. To take things a step further, [Laxman] sent the same requests, but changed the user’s ID to a victim account he had set up. The request was accepted and processed without a problem. This meant that [Laxman] could effectively delete photo albums from any other user without that user’s consent. The vulnerability did require that [Laxman] had permission to view the album in the first place.

Since [Laxman] is one of the good guys, he sent this bug in to the Facebook team. It took them less than a day to fix the issue and they rewarded [Laxman] $12,500 for his trouble. It’s always nice to be appreciated. The video below shows [Laxman] walking through how he pulled off this hack using Burp Suite. Continue reading “Deleting Facebook Albums Without Permission”

Remotely Controlling Automobiles Via Insecure Dongles

Automobiles are getting smarter and smarter. Nowadays many vehicles run on a mostly drive-by-wire system, meaning that a majority of the controls are electronically controlled. We’re not just talking about the window or seat adjustment controls, but also the instrument cluster, steering, brakes, and accelerator. These systems can make the driving experience better, but they also introduce an interesting avenue of attack. If the entire car is controlled by a computer, then what if an attacker were to gain control of that computer? You may think that’s nothing to worry about, because an attacker would have no way to remotely access your vehicle’s computer system. It turns out this isn’t so hard after all. Two recent research projects have shown that some ODBII dongles are very susceptible to attack.

The first was an attack on a device called Zubie. Zubie is a dongle that you can purchase to plug into your vehicle’s ODBII diagnostic port. The device can monitor sensor data from your vehicle and them perform logging and reporting back to your smart phone. It also includes a built-in GPRS modem to connect back to the Zubie cloud. One of the first things the Argus Security research team noticed when dissecting the Zubie was that it included what appeared to be a diagnostic port inside the ODBII connector.

Online documentation showed the researchers that this was a +2.8V UART serial port. They were able to communicate over this port with a computer with minimal effort. Once connected, they were presented with an AT command interface with no authentication. Next, the team decompiled all of the Python pyo files to get the original scripts. After reading through these, they were able to reverse engineer the communication protocols used for communication between the Zubie and the cloud. One particularly interesting finding was that the device was open for firmware updates every time it checked in with the cloud.

The team then setup a rogue cellular tower to perform a man in the middle attack against the Zubie. This allowed them to control the DNS address associated with the Zubie cloud. The Zubie then connected to the team’s own server and downloaded a fake update crafted by the research team. This acted as a trojan horse, which allowed the team to control various aspects of the vehicle remotely via the cellular connection. Functions included tracking the vehicle’s location, unlocking hte doors, and manipulating the instrument cluster. All of this can be done from anywhere in the world as long as the vehicle has a cellular signal.

A separate but similar project was also recently discussed by [Corey Thuen] at the S4x15 security conference. He didn’t attack the Zubie, but it was a similar device. If you are a Progressive insurance customer, you may know that the company offers a device that monitors your driving habits via the ODBII port called SnapShot. In exchange for you providing this data, the company may offer you lower rates. This device also has a cellular modem to upload data back to Progressive.

After some research, [Thuen] found that there were multiple security flaws in Progressive’s tracker. For one, the firmware is neither signed nor validated. On top of that, the system does not authenticate to the cellular network, or even encrypt its Internet traffic. This leaves the system wide open for a man in the middle attack. In fact, [Thuen] mentions that the system can be hacked by using a rogue cellular radio tower, just like the researchers did with the Zubie. [Thuen] didn’t take his research this far, but he likely doesn’t have too in order to prove his point.

The first research team provided their findings to Zubie who have supposedly fixed some of the issues. Progressive has made a statement that they hadn’t heard anything from [Thuen], but they would be happy to listen to his findings. There are far more devices on the market that perform these same functions. These are just two examples that have very similar security flaws. With that in mind, it’s very likely that others have similar issues as well. Hopefully with findings like this made public, these companies will start to take security more seriously before it turns into a big problem.

[Thanks Ellery]