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System Bus Radio: Transmits AM radio on computers without transmitting hardware

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Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#111

Post by meatmanek »

netsharc wrote: post #44
gtufano wrote: post #40

Earlier quoted context omitted.

Years ago I was in the same building during the installation of a "NATO standard" (whatever that means) environment suitable for developing sensitive software, and the air gap was indeed pretty large, the entire 2 rooms were air gapped from the building (at 4th floor), enclosed in a Faraday cage and with special precautions (out of my clearance level) for electricity going in. It was very quiet inside (even cell phon…

Hopefully cellphones weren't allowed? Otherwise it would be interesting to hack the phone to go to "record AM signals" if there's no cell/wifi/FM/GPS signals (if it were on a plane it would still see GPS signals). Or maybe to announce its presence using ultrasonic, so if there's also compromised machines/CPUs/hypervisor environments inside the secured environment, it would detect the "Hello" and start uploading data…

Have you seen the GSMem paper? They demonstrate pretty much exactly what you've proposed: https://www.usenix.org/node/190937

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#112

Post by j_s »

BuildTheRobots wrote: post #22

There's also PiFM[1] which (iirc) modulates one of the GPIO pins fast enough on a Pi to produce an FM radio signal. It's fun to play with, and is a great hack, but please don't try and use it for anything or any length of time; it puts out a tonne of horrible harmonics all over the radio spectrum. [1] https://github.com/rm-hull/pifm

> it puts out a tonne of horrible harmonics all over the radio spectrum

This is typically limited to a 50-100 foot radius without amplification, right?

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#113

Post by lovelearning »

randyrand wrote: post #108
lovelearning wrote: post #36

Earlier quoted context omitted.

Here's one. This sentence from the linked paper is informative - "When data is exchanged between the CPU and the RAM, radio waves are emitted from the bus's long parallel circuits." For some background: Digital circuits like computer motherboards have components called oscillators that switch voltage on and off a number of times every second. This is what "clock speeds" refers to - 2.8 GHz CPU clock speed means volta…

First realize the aptitude modulation in this radio is very crude. Unlike normal radio which has many amplitudes, this radio only has 2. On and off. Tone or no tone. This radio has no control over the exact amplitude. Due to this limitation, this radio can only transfer a single tone at a time. Music must be monophonic. To transfer a 60htz tone we just switch between the on and off state at 60htz. The On state will b…

Ah ok! So far, I was trying to unsuccessfully fit my mental model of normal amplitude modulation to what this code is doing.

Your two statements "This radio has no control over the exact amplitude. On state will be at some random amplitude that we can't control" were exactly the missing gaps I needed to clear my confusion. Very well explained, thank you very much!

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#114

Post by TeMPOraL »

dsign wrote: post #34

People had fanciful minds. They had expected the civilization to end in bio-warfare, or atomic bombs, or a blazing meteorite impact. No such luck. The end of the civilization came, rather anticlimactically, when the humans discovered that side effects and timing attacks made any form of cyber-security a joke. Their computers screeched to a halt bogged down by nightmarish security patches. By then, it was already too…

Side channels are always present. I think people not realizing it is a sad example of how our brains compartmentalize things, so that even smart individuals end up abstracting away the physical world.

These articles are only friendly reminders: computing runs in physical reality. Whatever you do, whatever information you process, its always broadcasting itself at the speed of light. The only thing you can do is to try and raise the practical costs of a side-channel attack so much, that it becomes much more expensive than the target data is worth to the attacker.

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#115

Post by TeMPOraL »

beamatronic wrote: post #43
dsign wrote: post #34

People had fanciful minds. They had expected the civilization to end in bio-warfare, or atomic bombs, or a blazing meteorite impact. No such luck. The end of the civilization came, rather anticlimactically, when the humans discovered that side effects and timing attacks made any form of cyber-security a joke. Their computers screeched to a halt bogged down by nightmarish security patches. By then, it was already too…

Or they just went back to using simple CPUs, and were content with solving smaller problems.

Nah, that wouldn't work - simple CPUs, by virtue of going slower, being less complicated inside and using more power per cycle, would be easier to snoop at through EM channels.

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#116

Post by TeMPOraL »

shabble wrote: post #94
c-smile wrote: post #74

Earlier quoted context omitted.

We were told about this by our lecturer in university (USSR). Discipline was "data protection / security" ("Защита данных" in Russian). The device was masqueraded as a canned "Килька черноморская в томате" (Canned fish: Black Sea sprat in tomato) and was transmitting short narrow beams upstream on schedule.

maybe something more like https://en.wikipedia.org/wiki/Acoustic_cryptanalysis ? I suppose it could be capturing EM emissions from the printers rather than acoustic, but that would make it fundamentally more like the other TEMPEST hacks as a way to exploit unintentional emissions, rather than as a sneaky covert channel where you have control over the computer equipment, but don't have access to external interfaces to…

With the printers and mainframes of old being big, couldn't it be just recording vibrations of the wall?

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#117

Post by 8bitsrule »

TeMPOraL wrote: post #115
beamatronic wrote: post #43

Earlier quoted context omitted.

Or they just went back to using simple CPUs, and were content with solving smaller problems.

Nah, that wouldn't work - simple CPUs, by virtue of going slower, being less complicated inside and using more power per cycle, would be easier to snoop at through EM channels.

And then, they discovered that by putting the 8-bit machines under metal rollers moving 12-foot-wide plastic film at 10 meters per second, their signals could not push through the resulting force field.

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#118

Post by closeparen »

gtufano wrote: post #40
cestith wrote: post #35

Back a couple of decades, my alphabetic pager was going off but the messages were gibberish. It turned out the CPU in the PC I'd been asked to look at was a Pentium running at 150 MHz. I'd set my pager directly on top of the case, and the nominal frequency for it was 150.5 MHz, frequency modulated. The lines in the motherboard can be used as antennae and the CPU pins can produce a clock pulse and modulate it. There u…

Years ago I was in the same building during the installation of a "NATO standard" (whatever that means) environment suitable for developing sensitive software, and the air gap was indeed pretty large, the entire 2 rooms were air gapped from the building (at 4th floor), enclosed in a Faraday cage and with special precautions (out of my clearance level) for electricity going in. It was very quiet inside (even cell phon…

A surprising amount of detail about SCIFs is public available [0].

[0] https://www.wbdg.org/FFC/DOD/UFC/ufc_4_010_05_2013_c1.pdf

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#119

Post by qubex »

tlb wrote: post #86
qubex wrote: post #76

Earlier quoted context omitted.

I know this is in good-natured jest, but wouldn’t the arrival of widespread quantum computing, which need to be absolutely decoupled from their environment so as to prevent decoherence, actually be an enormous step forward in almost all these “side channel” attacks? In the sense that decoupling must by definition limit any exchange of information that might constitute ‘observation’, and as such, the goings-on of a qu…

Current quantum computers don't have much in the way of microarchitecture. No caches or branch prediction obviously. But if you were timesharing on a quantum machine (which, given that they need $1M microkelvin coolers seems like it will be common) it's not impossible that information could leak. Given the analog way they work, you could probably set up a computation that would be sufficiently sensitive to initial co…

Uhm... no, I think not: to get information out of the quantum computer as output for the ”previous user” it needs to go through an explicit phase of observation, busting all the state (?), and loading up new data for the subsequent user’s computation also constitutes ’observation’ since there’s knowledge of the inner state of the quantum system outside the strict confines of the quantum system. I really don’t think you could at any moment in time get information out of a side-channel, otherwise the thing wouldn’t compute.

(Yup, of course they’re extremely simplistic in terms of inner architecture, but that’s quite beside the point, as I think we both agree.)

Re: System Bus Radio: Transmits AM radio on computers without transmitting hardware

#120

Post by Piskvorrr »

xenadu02 wrote: post #67
c-smile wrote: post #57

Quite old trick actually. At Cold War time, in USSR, American spy device was discovered that was placed on the street outside the wall of main frame computer installation nearby drum printers ( https://en.wikipedia.org/wiki/Printer_(computing)#/media/Fil... ). The device was recording signals from them and retransmitted recording in compressed form to satellite.

Do you have a link to more information about this?

It does sound very similar to the Selectric hack - similar capabilities existed on both sides of the Iron Curtain, one would guess.

https://arstechnica.com/information-technology/2015/10/how-s...

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