Does anyone else get the feeling that the frequency of rather horrible vulnerabilities coming to light is accelerating? Off the top of our head, there’s Heartbleed, Shellshock, and now this one. The BadUSB exploit attack stems from the “invisible” microcontroller in most USB devices.
We first heard about it when we were attending DEFCON in August. The exploit had been announced the same week at Blackhat but there wasn’t much information out yet. Now the talk has been posted and there’s a well-explained overview article at Big Mess o’ Wires.
Here’s how this one goes: all USB devices rely on a microcontroller to handle the peripheral-side of USB communications. The computer doesn’t care which microcontroller, nor does it have a way of knowing even if it wanted to. The uC is “invisible” in this situation, it’s the interface and data flowing through it that the computer cares about. BadUSB is an attack that adds malicious functionality to this microcontroller. To the computer it’s a perfectly normal and functional USB device, while all the bad stuff is happening on the peripheral’s controller where the computer can’t see it.
How deeply do you think about plugging each and every USB device? Check out what happens at 19:20 into the video below. The USB device enumerates and very quickly sets up a spoofed Ethernet connection. You can still load a webpage via WiFi but the fake connection is forwarding packets to a second server.
Once discovered, you can wipe the computer and this will stop happening; until you plug the same device again and reinfect. Worse yet, because the controller is invisible to the computer there’s almost no way to scan for infected devices. If you are smart enough to suspect BadUSB, how long will it take you to figure out if its your mouse, your keyboard, a thumb drive, a webcam, your scanner… you get the point.
Continue reading “BadUSB Means We’re All Screwed”
A team of researchers from Georgia Tech unveiled their findings yesterday at the Blackhat conference. Their topic is a power charger exploit that installs malware on iOS devices. Who would have thought that there’d be a security hole associated with the charging port on a device? Oh wait, after seeing hotel room locks exploited through their power jack this is an avenue that should be examined with all device security.
The demonstration used a charger and an BeagleBoard. Plugging in the charger is not enough to trigger the exploit, the user must unlock the screen while charging for it to go into action. But once that’s done the game is over. Their demo removes the Facebook app and replaces it with an infected impostor while leaving the icon in the same place on your home screen. They notified Apple of their findings and a patch will roll out with iOS7. So when would you plug your device into an untrusted charger? Their research includes a photo from an airport where an iPad is connected to the USB port of a public charging station.
The summary on the Blackhat site has download icons for the white paper and presentation slides. At the time of writing we had a hard time getting them to download but succeeded after several tries.
Check out this jumbled confirmation window. At first glance the message appears to contain a bunch of gibberish, but it can actually be read if you start at the right side and read each character moving left. The text displays like this because it is prefixed by a special Right-to-Left override Unicode character. The technique is being used in malware to obscure the actual extension of the file being launched. Notice that when written backwards your eye can still pick out the string “pdf” which may be enough to trick the uninitiated into approving the launch of the file.
This confirmation screen is launched when clicking on a piece of malware found in the wild a little over a week ago. If you do choose to run it, a decoy PDF file is opened in order not to arouse suspicion. But at the same time the program — which is signed with an Apple Developer ID — is installing itself in the home directory and making a cron job to launch at each boot. Sneaky!
When you think about hacking laptops, it’s highly unlikely that you would ever consider the battery as a viable attack vector. Security researcher [Charlie Miller] however, has been hard at work showing just how big a vulnerability they can be.
As we have been discussing recently, the care and feeding of many batteries, big and small, is handled by some sort of microcontroller. [Charlie] found that a 2009 update issued by Apple to fix some lingering MacBook power issues used one of two passwords to write data to the battery controllers. From what he has seen, it seems these same passwords have been used on all batteries manufactured since that time as well. Using this data, he was subsequently able to gain access to the chips, allowing him to remotely brick the batteries, falsify data sent to the OS, and completely replace the stock firmware with that of his own.
He says that it would be possible for an attacker to inject malware into the battery itself, which would covertly re-infect the machine, despite all traditional removal attempts. Of course, replacing the battery would rectify the issue in these situations, but he says that it would likely be the last thing anyone would suspect as the source of infection. While using the battery to proliferate malware or cause irreversible damage to the computer would take quite a bit of work, [Charlie] claims that either scenario is completely plausible.
He plans on presenting his research at this year’s Black Hat security conference in August, but in the meantime he has created a utility that generates a completely random password for your Mac’s battery. He says that he has already contacted Apple to in order to help them construct a permanent fix for the issue, so an official patch may be available in the near future.
While some people know that you should be wary of USB drives with unknown origins, the same care is rarely, if ever exercised with USB peripherals. The security firm Netragard recently used this to their advantage when performing a penetration test at a client’s facility. When the client ruled out the use of many common attack vectors including social networks, telephones, social engineering, and unauthorized physical access from the test, the team at Netragard knew they would have to get creative.
They purchased a Logitech USB mouse and disassembled it in order to add their clever payload. A Teensy uC was programmed to emulate keyboard input, entering commands via the mouse’s USB connection once it had been connected to a computer. Using an undocumented exploit in McAfee’s antivirus suite, they were able to evade detection while their system entered commands to install malware from the flash drive they hid along side the Teensy.
Once the mouse was reassembled, they repackaged it along with some marketing materials to make it look like part of a promotional event. They purchased a detailed list of employees and singled out an easy target, sending their malicious mouse on its way. Within three days, their malware was loaded onto the victim’s computer and their test was deemed a success.
[Dino A. Dai Zovi] gave a talk in the earlier part of 2010 where he shares his thoughts on the future of malicious exploits. You can watch it on Ustream and he’s also posted a set of slides (PDF) that goes along with it. We find the 48 minute video to be quite interested. Instead of going into mundane detail, he covers the broader picture; what has been done in the past, what will happen in the future, and how are we currently ill-equipped to respond to future threats? That last question is covered throughout the video, but seems to come back to the concept that we are stuck in a rut of terminology and past practice that is impeding our ability to innovate security strategies at the same rate that the bad guys are coming up with the next nasty thing to come down the pipeline.
When a new virus or other piece of malware is identified, security researchers attempt to get a hold of the infection toolkit used by malicious users, and then apply this infection into a specially controlled environment in order to study how the virus spreads and communicates. Normally, these toolkits also include some sort of management console commonly used to evaluate successfulness of infection and other factors of the malware application. In the case of the EFTPS Malware campaign however, the admin console had a special trick.
This console was actually a fake, accepting a number of generic passwords and user accounts, and provide fake statistics to whoever looked in to it. All the while, the console would “call home” with as much data about the researcher as possible. By tricking the researchers in this way, the crooks would be able to stay one step ahead of anti-virus tools that would limit the effectiveness of any exploit. Thankfully though, the researchers managed to come out on top this time.