Intentional EMI (IEMI) is an emerging phenomenon which has been causing facility operators and infrastructure stakeholders to re-think their approaches to network and site installation design. Essentially, IEMI consists of the deliberate coupling of electromagnetic energy into a system or facility in order to impair, damage or manipulate the facility or system in some way. Similar in intent to a cyber attack, an IEMI event may be intended to simply compromise the facility owner or operator, but attempts have been made to use IEMI to access and steal data from a victim system, or even to manipulate or corrupt system data in a precise and deliberate manner (IEMI Threats for Information Security: Remote Command Injection on Modern Smartphones). In 2020, Belgian researchers at were able to demonstrate that they could re-construct the images on a hidden video monitor simply by directing an antenna towards the HDMI cable connecting the monitor to its computer and analyzing the ‘captured’ EM emissions (EMC Magazine 2nd quarter 2021).
The danger of IEMI is that it can access a system from outside that system as long as it has some physical means for its interference signals to propagate to its target. This means could be cabling or metallic structures of any kind, or just an unshielded path over the airwaves. A broadband signal would likely be used if the attackers have limited knowledge about the target, but a specific narrow band pulse would be more effective if the nature of their target and its intended coupling path were well understood by them. In either case, the best defence against IEMI is basically the same as it would be for EMI: characterize the electromagnetic properties of the networks and installations, and its potential vulnerabilities, and then implement an effective strategy of shielding, filtering, grounding and component isolation. In some jurisdictions, regulatory or recommended standards have been coming into effect to ensure that new and existing facilities are protected against IEMI. (Protecting Industry from HEMP and IEMI)