PIXHELL Attack: Leaking Information from Air-Gap Computers via `Singing Pixels'

PIXHELL is a covert channel attack that leaks data from air-gapped and audio-gapped computers through acoustic noise generated by screen pixels, without requiring audio hardware or loudspeakers. Malware generates crafted pixel patterns that produce noise in the 0 to 22 kHz range, exploiting sound from the coils and capacitors that control screen frequencies. According to the paper's tests, textual and binary data can be exfiltrated at a distance of 2 meters via sound modulated from LCD screens. The paper also covers low-brightness patterns that appear like turned-off screens for evasion and proposes countermeasures.