How an ancient printer can spill your most intimate secrets

"Researchers have devised a novel way to recover confidential messages processed in doctors' offices and elsewhere by analyzing the sounds made when documents are reproduced on dot-matrix printers.

This so-called side-channel attack works by recording the "acoustic emanations" of a confidential document being printed, and then processing it with software that translates the sounds into words. The method recovers as much as 95 per cent of the printed words when an attacker has contextual...