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Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

arxiv.org

1–10 of 32 posts

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#2
In some alternate timeline, there's yet another attack vector of noise from still-in-use floppy drives. (In addition to other less-obsoleted things like flatbed scanners.)

Much the same way that people have used them to make music.

https://www.theverge.com/24034551/floppy-disk-music-scene-un...

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#3
For those unindoctrinated with the underlying phenomenon being exploited, this demo[1] was shared almost a decade ago.

Also, undiscussed mitigation techniques[2] relevant to this general class of nuisance that circuit designers may find of value.

[1] https://news.ycombinator.com/item?id=8862689

[2] https://news.ycombinator.com/item?id=41505772

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#4
post #2

In some alternate timeline, there's yet another attack vector of noise from still-in-use floppy drives. (In addition to other less-obsoleted things like flatbed scanners.) Much the same way that people have used them to make music. https://www.theverge.com/24034551/floppy-disk-music-scene-un...

Not an alternate timeline, I went to a blackhat talk that was exfiltrating data from airgapped computers with unconnected parallel port pins, printers (exact same thing as making them make music but faster and with EM), and other peripherals. At a usable distance of some meters too.

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#5
Two meters seems like a pretty short distance to bypass an airgap.

At that point, in the kind of situation where someone is actively trying to exfiltrate data, couldn't they point their phone camera at a screen?

Like, maybe there are scenarios where the exit device is compromised without the wearer knowing, or the spy wants to remain discrete, but they seem a bit niche.

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#6
post #3

For those unindoctrinated with the underlying phenomenon being exploited, this demo[1] was shared almost a decade ago. Also, undiscussed mitigation techniques[2] relevant to this general class of nuisance that circuit designers may find of value. [1] https://news.ycombinator.com/item?id=8862689 [2] https://news.ycombinator.com/item?id=41505772

That just blew me away! I didn't think I was going to hear anything, but yeah, immediately it gave an almost pulse-width modulated high pitch tone. I'm not surprised, but it is also awesome. I'm so many years old yet I can still hear the hum from CRT's, but I'd say that tone is much higher frequency.

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#7

Two meters seems like a pretty short distance to bypass an airgap. At that point, in the kind of situation where someone is actively trying to exfiltrate data, couldn't they point their phone camera at a screen? Like, maybe there are scenarios where the exit device is compromised without the wearer knowing, or the spy wants to remain discrete, but they seem a bit niche.

Two ways this is useful:

- It is possible that the airgapped system still has a publicly viewable screen displaying harmless information. But you use this technique to leak secret information from the system.

- If the authors established that 2m is the maximum distance that you can reliably leak information this way, then that is in principle useful information for someone designing the security system. No audio recording software allowed within 2m of the screen!

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#8
My uncle described the air gapped facility he worked in… when they said no EM out, they meant nothing in or out except humans and filtered air. It was behind dual interlocking nuclear blast doors and concrete. Even the water was sourced and recycled on site to prevent documents or capsules exfiltration via the sewer.

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#9

Two meters seems like a pretty short distance to bypass an airgap. At that point, in the kind of situation where someone is actively trying to exfiltrate data, couldn't they point their phone camera at a screen? Like, maybe there are scenarios where the exit device is compromised without the wearer knowing, or the spy wants to remain discrete, but they seem a bit niche.

[dead]

Re: Pixhell Attack: Leaking Info from Air-Gap Computers via 'Singing Pixels'

#10
post #2

In some alternate timeline, there's yet another attack vector of noise from still-in-use floppy drives. (In addition to other less-obsoleted things like flatbed scanners.) Much the same way that people have used them to make music. https://www.theverge.com/24034551/floppy-disk-music-scene-un...

Not an alternate timeline, I went to a blackhat talk that was exfiltrating data from airgapped computers with unconnected parallel port pins, printers (exact same thing as making them make music but faster and with EM), and other peripherals. At a usable distance of some meters too.

You can broadcast FM radio over short distances by doing PWM over GPIO pins, so that does not suprise me!

I used this for switching radio controlled power outlets which had 433mhz receivers. [2]

[1] https://github.com/markondej/fm_transmitter?tab=readme-ov-fi...

[2] https://github.com/F5OEO/rpitx

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