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Scientist-developed malware covertly jumps air gaps using inaudible sound

arstechnica.com

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Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#41

Post by benihana »

NovaS1X wrote: post #35
TrainedMonkey wrote: post #11

Earlier quoted context omitted.

20 bits = 2 and a half bytes, and you are right that is enough. What surprises me is how people regarding this as "novel" not too long ago quite a few people used a "modem". That was a mythical device that used phone networks to transmit information. Regular phones would pick up that as sound. Sure there are few technical hurdles - covert communication and stringent error correction are most visible, but concepts are…

It's surprising how many people either forget about modems or never had internet in the days of modems. I've had numerous nerdy conversations and theory crafting scenarios where someone will bring up the crazy idea of using sound to transmit data. I'm just like "Yeah, we've done that already. Remember dialup?".

>It's surprising how many people either forget about modems or never had internet in the days of modems.

Pardon the snark, but what is surprising about that? Every person with access to the internet born since about 1997* will have no memory of using dialup. The ratio of people who used dialup relative to the people on the internet is going to continue to dwindle rapidly from here on out. Even then, I probably spent 6 or 7 years dialing up, and the connection of that to this story never happened in my brain.

* say 2003-2004 was when broadband went mainstream, at that point, people born in 1997 will be 6-7 years old.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#42

Post by mbell »

bane wrote: post #40
mbell wrote: post #36

Earlier quoted context omitted.

Most 'white noise generators' aren't producing white noise. White noise has equal power in each linear band, e.g. 100Hz to 120Hz would have the same spectral power as 19,000Hz to 19,020Hz. Humans hear in a logarithmic fashion so real white noise is actually incredibly annoying to listen to. To the ear it has a lot of high frequency content in it, it sounds like a high frequency fuzz. Most 'white noise generators' are…

Thanks for the great comment! Anybody interested in the noise colors might take an interest in http://playnoise.com/ (hint, hit more and enable stereo, I find that much more interesting for some reason). Also http://en.wikipedia.org/wiki/Colors_of_noise

> (hint, hit more and enable stereo, I find that much more interesting for some reason)

I haven't played with this site in particular but they are probably using incoherent sources for each channel. i.e. using two separate random noise generators that aren't working off the same seed value. Even though the spectral content of each channel may be the same, it's not the same at any instant which causes your brain to get a bit 'lost', it doesn't sound like a point source anymore but instead just a 'room filling' sound that you can't pin point. The same principal (in a more targeted manner) is used in mixing stereo music to create a 'sound stage', usually only the voice mix is actually identical in both channels even though you can hear the guitar in each channel independently.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#43

Post by ENGNR »

It's scary just how much SCADA software (electricity, water, fuel, prisons, etc) is absolutely ridden with vulnerabilities, protected ONLY by that air gap. Typically this internal network will be accessed by terminals sitting immediately adjacent to terminals on the more general network (so a user can quickly switch between them over the air gap).

They'd both need to be infected it's true, but that is quite achievable with USB social engineering or if an attacker can gain physical access to any of the terminals on the network. If that were the case then an attacker could get any information out that they wanted (flight data, prison routines, defence asset refueling movements, even just information enumeration and vulnerabilities in the network).

The terminal probably wouldn't have a microphone it's true (typically very old hardware that everyone is too scared to upgrade), but if it did it would also give remote trigger access to abuse that infrastructure.

It's actually good information for security architects. If you can't get approval to start using software updates, make sure your damn microphones are turned off.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#44

Post by joe_the_user »

teraflop wrote: post #2

Note that using ultrasound as a communication mechanism, which is what's being described here, is very different from using it as an infection vector .

Yes,

It's not as significant as one might imagine.

But it does have the significance that you still have to worry whether your air-gapped machine is infected since it could secretly leak info even unplugged.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#45

Post by StavrosK »

mikeash wrote: post #34
TrainedMonkey wrote: post #11

Earlier quoted context omitted.

20 bits = 2 and a half bytes, and you are right that is enough. What surprises me is how people regarding this as "novel" not too long ago quite a few people used a "modem". That was a mythical device that used phone networks to transmit information. Regular phones would pick up that as sound. Sure there are few technical hurdles - covert communication and stringent error correction are most visible, but concepts are…

Beyond modems, there are also some obscure biological machines that transmit information by modulating sound waves in the air that have been around for some millions of years.

But surely they must have spent hundreds of millions of years transmitting the information in written form before mastering acoustic transmission?

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#46

Post by piggity »

TrainedMonkey wrote: post #11
devindotcom wrote: post #4

I love this sci-fi by way of anachronism stuff. The transfer rate of ~20 bytes per second is tiny, but of course that tiny amount could be the difference between two machines appearing to communicate and not appearing to. If your network traffic is confirmed to be zero, that's a state of confidence that's easy to take advantage of, and a deeply-rooted bit of malware like this could strike in extremely subtle and devi…

20 bits = 2 and a half bytes, and you are right that is enough. What surprises me is how people regarding this as "novel" not too long ago quite a few people used a "modem". That was a mythical device that used phone networks to transmit information. Regular phones would pick up that as sound. Sure there are few technical hurdles - covert communication and stringent error correction are most visible, but concepts are…

The old Polar series of sports monitoring watches (HRM/speed/cadence etc) used to transmit data using a "Sonic Link".

e.g. client library - https://code.google.com/p/sonicread/

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#47

Post by 4ad »

ENGNR wrote: post #43

It's scary just how much SCADA software (electricity, water, fuel, prisons, etc) is absolutely ridden with vulnerabilities, protected ONLY by that air gap. Typically this internal network will be accessed by terminals sitting immediately adjacent to terminals on the more general network (so a user can quickly switch between them over the air gap). They'd both need to be infected it's true, but that is quite achievabl…

> SCADA [...] is absolutely ridden with vulnerabilities, protected ONLY by that air gap.

That's some wishful thinking.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#48

Post by mikeash »

StavrosK wrote: post #45
mikeash wrote: post #34

Earlier quoted context omitted.

Beyond modems, there are also some obscure biological machines that transmit information by modulating sound waves in the air that have been around for some millions of years.

But surely they must have spent hundreds of millions of years transmitting the information in written form before mastering acoustic transmission?

It makes logical sense, so it must be true!

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#49

Post by smtddr »

privong wrote: post #16
JackFr wrote: post #10

Keep your headphones plugged in. BAM! Solved!

This just shows my ignorance with regard to this topic, but is the speaker cutoff from plugging in headphones always a hardware switch? I.e., can software override it and direct sound to the speakers even if one has headphones plugged in? Of course, if one were playing music or something, it would be obvious that the switch had been circumvented.

http://i.imgur.com/ip6zwes.png

On Linux you can choose different behavior; so it's apparently software. At least, on machines I've worked on. Depending on that dropdown, I can plug in headphones and the built-in speakers will continue to output.

Re: Scientist-developed malware covertly jumps air gaps using inaudible sound

#50

Post by sanderjd »

NovaS1X wrote: post #35
TrainedMonkey wrote: post #11

Earlier quoted context omitted.

20 bits = 2 and a half bytes, and you are right that is enough. What surprises me is how people regarding this as "novel" not too long ago quite a few people used a "modem". That was a mythical device that used phone networks to transmit information. Regular phones would pick up that as sound. Sure there are few technical hurdles - covert communication and stringent error correction are most visible, but concepts are…

It's surprising how many people either forget about modems or never had internet in the days of modems. I've had numerous nerdy conversations and theory crafting scenarios where someone will bring up the crazy idea of using sound to transmit data. I'm just like "Yeah, we've done that already. Remember dialup?".

Also, modems didn't really seem very different from ethernet. My initial reaction as an early adolescent to first encountering ethernet was along the lines of, "oh, so it's just a wider port? what's all the fuss about?" Besides all the funny noises on connection (which, as an aside - why did the handshake have to actually be audible?), everything seemed to work the same, just more slowly. You don't have to forget about modems to be unaware that using sound to transmit computer data was once common.
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