A concealed recording device is a hidden microphone, voice recorder, or similar gadget used to capture speech without the target noticing. It may be built into everyday objects or placed out of sight, making it hard to detect during normal use of a room.
In cyber security, this matters because not all data theft happens through networks. A hidden recorder can capture passwords spoken aloud, product plans, incident response details, or other sensitive discussions, creating information leakage without malware or log traces. Attackers may use it for insider spying, extortion, or competitive intelligence, while defenders reduce the risk with physical access controls, device bans in sensitive areas, and regular security sweeps for unauthorized hardware. The term is a reminder that meeting rooms, offices, and labs are part of the attack surface too.