A flaw in the Android MediaProjection service could be exploited by an attacker to record audio and screen activity on around 77.5% of all Android devices. A vulnerability affecting Android smartphones running Lolipop, Marshmallow, and Nougat could be exploitable. The root cause of this vulnerability is due to the fact that vulnerable Android versions dont implement mechanisms to detect partially obscured SystemUI pop-ups. Older versions of Android Oreo (8.0), older versions are still affected by the bug.”]
Source: http://securityaffairs.co/wordpress/65786/hacking/android-mediaprojection-service-bug.html