The SHAREit application before 4.0.36 for Android allows a remote attacker (on the same network or joining public “open” Wi-Fi hotspots created by the application when file transfer is initiated) to bypass authentication by trying to fetch a non-existing page. When the non-existing page is requested, the application responds with a 200 status code and empty page, and adds the requesting client device into the list of recognized devices.
Source: NIST