Patrick Wardle, an ex-NSA staffer who heads up research at security intelligence firm Synack, discovered a way for Mac malware to tap into your live feeds from Mac’s built-in webcam and microphone to locally record you even without detection. Mac’s firmware-level protection lights the green LED for any unauthorized access to user’s webcam, Wardle believes that attackers can use a malicious app that quietly monitors the system for any outgoing feed of an existing webcam session. The malware then piggybacks the victim’s webcam or microphone to secretly record both audio and video sessions without any visible indication of this malicious activity and any fear of detection.
Source: https://thehackernews.com/2016/10/macbook-camera-hacked.html