Revealed: Your computer could be hacked by using only sound waves
New Delhi: The most secure computers in the world are completely isolated from other machines—protected by “air gaps,” with no Internet connection, no shared phone lines, nothing. Conventional wisdom goes that such computers are impossible
Building upon preexisting technology used to transmit data under water by sound waves, the researchers were able to use the microphone and speakers in an unmodified Lenovo T400 personal computer to transmit small amounts of information—keystrokes in the test case, though the hack could also transmit encryption keys, small text files and even passwords—from an isolated computer to a compromised one.