"As first reported by Ars Technica, these hackers have developed a new twist on the old military technique, known by the National Security Agency codename of TEMPEST, of spying through the use of leaking emanations. Of these, the ability to eavesdrop by way of a laser microphone beamed onto a window as used during the Cold War era is perhaps the most well-reported.
This has the drawback of being an active attack, with that laser beam having to illuminate the surface and so being open to easy detection. The newly reported surveillance methodology, however, is passive in nature."
https://www.forbes.com/sites/daveywinder/2021/08/15/hackers-use-flickering-power-leds-to-spy-on-conversations-100-feet-away/?sh=639c08945301
"Security researchers based at the Ben-Gurion University of the Negev and the Weizmann Institute of Science in Israel, have been looking at methods of eavesdropping on private conversations without needing to compromise a device with malware first. This type of hacking research isn't unique, and only last year, it was revealed that Alexa, Google Home, and Siri could potentially be compromised using lasers pointed at the device microphones. But this latest research goes beyond merely turning a device on or off as was the case with the laser pointer exploit. Indeed, these bright hackers don't even need the victim of the eavesdrop to be using a "smart" device in the first place. As long as there's a "dumb" but essential light bulb in the same room, it's all systems go. Well, sort of."
https://www.forbes.com/sites/daveywinder/2020/06/14/how-to-use-an-ordinary-light-bulb-to-spy-on-conversation-80-feet-away-security-research-lamphone-hack/?sh=40f2e5615be1
"This technique, dubbed as “Lamphone Attack”, shows that a conversation can be eavesdropped from about 25 metres (82 feet) away if there is a hanging light bulb near the location of the conversation. It works by detecting vibrations produced from bulbs due to the fluctuation of air pressure caused by the sound waves. When the sound waves hit the surface of the room, it triggers small vibrations that can be picked up through an electro-optical sensor focused at the bulb, say the scientists. This can then be used to pick up a conversation."
https://www.vice.com/en/article/m7jbq3/hackers-can-spy-on-your-conversations-through-an-ordinary-light-bulb
Hackers can use an ordinary light bulb in your room to spy on you. Here's how
https://www.livemint.com/technology/tech-news/hackers-can-use-an-ordinary-light-bulb-in-your-room-to-spy-on-you-here-s-how-11592364141655.html