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Researchers Build Covert Acoustical Mesh Networks In Air
An anonymous reader writes "Researchers at Fraunhofer FKIE, Germany have presented a paper on covert acoustical communications between laptop computers. In their paper 'On Covert Acoustical Mesh Networks in Air', they describe how acoustical communication can be used to secretly bridge air gaps between computers and connect computers and networks that are thought to be completely isolated from each other. By using ad-hoc routing protocols, they are able to build up a complete mesh network of infected computers that leaks data over multiple hops. A multi-hop acoustical keylogger is also presented where keystrokes are forwarded to an attacker over multiple hops between different office rooms. The fundamental part of the communication system is a piece of software that has originally been developed for acoustic underwater communications. The researchers also provide different countermeasures against malicious participation in a covert acoustical network. The limitations of air gaps have been discussed recently in the context of a highly advanced malware, although reports on this so-called badBIOS malware could not yet be confirmed."
It's called AirPort.
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White noise generator
An "air gap" means making sue a computer cannot exchange information with other computers. LAN is one way to do so, but other sensors on the computer can be used for input, and other devices for output. Is it really a surprise that the microphone on a computer can be used as an input device?
Soon we'll have marketers pitching space-gapped machines, so even the acoustics are blocked.
I am really surprised so much in the way of audio electronics in computers lacks a bandpass filter to prevent interference from stuff outside of the audible spectrum.
Air gaps are a liability. They do not work as advertised. Covert audio channels have nothing to do with it.
When you put a computer in a faraday cage with an air gap, you still need to computer to have some input and output in order to be useful.
So the air gap requires that a human periodically walks into the room and interacts with the machine. At this point, the options for undermining the security of the system have gone up exponentially.
The reality of air gaps is that key signing ceremonies take place with several people packed in the room, while CDs are passed back and forth and put in the machine holding the CSRs, the software and signed certs.
If you instead had a wire to the machine in the room, you could monitor the transactions over the wire. You could ensure a non turing complete language is used in the wire protocol. You can deny humans access. You can apply defense in depth to a wire. No so much to a room full of humans.
Air gaps are evil.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
They used Lenovo T400 laptops which are circa 2008 models, no extra audio hardware. They could do 20bits/sec over nearly meters 20 meters if they had line-of-site between the laptops.
When information is power, privacy is freedom.
Oh great... Can't you hackers just leave well enough alone?
I've had to disconnect my network cable, remove the wireless card, and disable all the USB ports to make my machine secure and now I have to disable the audio hardware too? Man, this is getting out of hand..
Seriously though... This is new how? We have been sending data using audio cards between computers for decades. I remember cranking up the cassette tape drive to load programs into my TRS-80 in high school and hooking up to an acoustic modem to get on dial up AOL. Recently I've used my computer to talk to another computer halfway around the world though an RF link provided by my ham radio. Hams routinely transfer "data" over packet, PSK and other modes over audio links using their audio cards in their computers.
Oh, wait, so the ad-hock links are the new thing? Um, not so fast there either. Mesh networks have been around long enough to fall in and out of favor once or twice. Ham radio operators might know about HSMM Mesh http://www.broadband-hamnet.org/ has been doing mesh networks for nearly a decade, and the protocol it uses internally wasn't the first. So this is not new..
I conclude that NOTHING here is new, except perhaps combining an audio network link with a mesh networking protocol.... But I don't see that as ground breaking..
The only thing this will really do is make it necessary to disable/remove audio hardware from secure computers, just because somebody might try to use it for something stupid. Thanks guys (and gals if there are any working on this) for making my life harder...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
No one can hear this going on?
OH. MY. GOD. Air gaps.
I thought my tinfoil hat was sufficient, but you're telling me I now have to worry about sounds going in my ears that modify my behavior!?!?!
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Without the software required to use the hardware for communication, the communication doesn't work. If your air-gapped computer has not been infected prior to air-gapping, this simply can't work. I can smell conspiracy theorists a mile away with "but what about malicious BIOSes or pre-infected hardware designs or..." and the solution for all of those remains the same: if it's that big of a concern, remove it from the computer. Rip open the laptop and disconnect or desolder the speakers and microphone, and while you're in there you can heat-gun off the magnetics for the network card and all the external USB port connectors. If you're gonna do paranoid, you might as well do it right.
Not only is it not new, I remember almost 10 years ago now, somebody had demonstrated that he could slam the bus in such a way as to generate radio signals that he could pick up on a nearby reciever.
There was even a slashdot story about it back then, but damned if I can find anything on it now. Pretty sure it was only a one way channel but, depending on the circumstances, that could be enough.
"I opened my eyes, and everything went dark again"
If malware dint use it before, its sure going to use it soon enough after this paper.
Finally employers are motivated enough to offer silent office spaces for every employee. The silence of the machines is a desirable feature, even without Jodie Foster - Arnold Schwarzenegger team-up.
Exactly. And Bruce Schneier has an excellent article on that concept. He calls it "attack trees".
https://www.schneier.com/paper-attacktrees-ddj-ft.html
I think that the biggest problem here is that there isn't a recognized definition of "security" as it applies to computers.
Security is not about becoming invulnerable. That is impossible. Mostly because there is no "secure". There is only "more secure" or "less secure" than your starting point.
Improving security is, initially, about reducing the number of people who can EFFECTIVELY attack you. Then increase the number of people REQUIRED to attack you.
And that isn't even addressing the issue of whether you KNOW that you're being attacked and/or whether the data has been compromised.
Interesting timing, considering the recent exposure (and debunking?) of BadBIOS "acoustical networking".
So, dogs will bark constantly when these devises are attempting to communicate? Bring Rover in to work with you. Problem solved.
"The ferrets, they're every where I tell you!"
How much are you getting paid for this offtopic claptrap on every post? At least the "Cruz Control" guy who spews stuff how NASA should be privatized, has tried to make posts fairly relevant to the topic hand before going into how deeply in debt we are in with China.
There was a tenant from the old Soviets. Tell a lie often enough, and people will start believing it. Guess this is working.
"Tell a lie often enough, and people will start believing it. Guess this is working."
It's not just a Soviet axiom, it's also part of Alinskys rules. So I take it you see right through the bullshit then huh? Yes Obama knows his Alinsky as well as anyone could.
“If you push a negative hard enough, it will push through and become a positive.”
A few weeks ago, we all read about a new form of malware that uses acoustics, and now we have "researchers" doing writeups and building networks so soon? Hmmm. Something smells fishy here.
Why my network crashed when I farted!
This message was not sent from an iPhone because Peter Sellers really was a deviated prevert without a dime for the call
back in the day — with TRS80 300 baud cassette loading — we thought 300 bps was pretty SSSSLLLOOOWWW..
they managed the blazing speed 20bps (bits per second) at 3 meters using 18khz carrier frequency — and that had a faint clicking sound.
20 bps is slower than most people type — you're not going to be transmitting any high-res jpeg images this way..
good enough to capture and transmit a password though, or to do command-control type actions.
heh heh — transmitting a spy app between nodes as a payload could take weeks..
when they made it quieter so you couldnt hear the slight clicking sound — the range was http://www.jocm.us/uploadfile/2013/1125/20131125103803901.pdf
The smallest viruses are well within the storage capacity of a QR code, and an exploit could be a mere handful of bytes; what makes you think that they are somehow inherently secure?
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
FM radio transmissions are possible on the R.Pi by toggling the spread-spectrum setting of a clock output pin.
http://www.icrobotics.co.uk/wiki/index.php/Turning_the_Raspberry_Pi_Into_an_FM_Transmitter
"Covert acoustical mesh networks"?!? Housewives invented this thousands of years ago, only back then they called it "gossip."
Give me my freedom, and I'll take care of my own security, thank you.