BSI ID: G 0.13

Electrical devices emit electromagnetic waves. In devices that process information (e.g. computers, monitors, network coupling elements, printers), this radiation can also carry the information that is currently being processed. Such information-carrying radiation is called compromising radiation. An attacker located in a neighbouring house or in a vehicle parked nearby, for example, can attempt to receive this radiation and reconstruct the processed information from it. This compromises the confidentiality of the information. A possible objective of such an attack is industrial espionage.

The limits set by the Electromagnetic Compatibility of Equipment Act (EMVG) are generally not sufficient to prevent the interception of compromising emissions. If this risk cannot be accepted, additional protective measures must therefore be taken as a rule. Compromising emissions are not limited to electromagnetic waves. Under certain circumstances, useful information can also be obtained from sound waves, for example from printers or keyboards. It should also be noted that, in certain cases, compromising radiation can also be caused or amplified by external manipulation of devices. If, for example, a device is irradiated with electromagnetic waves, the reflected waves may carry confidential information.