G 0.13 Interception of compromising radiation

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 currently being processed. Such information-carrying radiation is called emanations or compromising radiation. An attacker, who for example is in a neighboring building or in a parked vehicle nearby, may attempt to receive this radiation and reconstruct the information being processed from it. The confidentiality of the information is thus called into question. A possible objective of such an attack is industrial espionage.

The limit values of the Electromagnetic Compatibility Act (EMVG) are generally insufficient to prevent the interception of emanations. If this risk cannot be accepted, additional protective measures must therefore generally be taken.

Emanations are not limited to electromagnetic waves. Useful information can also be obtained from sound waves, for example from printers or keyboards.

It should also be noted that emanations can in certain cases be caused or amplified by external manipulation of devices. For example, if a device is irradiated with electromagnetic waves, the reflected waves may carry confidential information.