Security professionals only consider software vulnerabilities when considering the risks of connecting devices to their networks and systems. This document considers the potential risk posed by hardware modification of seemingly innocuous hardware devices attached to critical systems, by showing how a simple KVM switch can be modified for use as a key logger. The Internet of Things is an example of the potential risks posed by a simple simple switch can easily be used to record a keylogger in a secure environment. The document is published by security experts at the Open Source Security Initiative.”]
Source: https://labs.portcullis.co.uk/whitepapers/hacking-the-belkin-e-series-omniview-2-port-kvm-switch/