It looks like Modzero has helped BlackBerry discover a vulnerability in the way BlackBerry 10 implements file sharing over Wi-Fi. This vulnerability allows attackers on the same Wi-Fi network to possibly access shared files on your device even if you have a password setup for sharing. So far this vulnerability is not being exploited in the wild but it is present on all BlackBerry 10 devices before OS 10.2.1.1925.
Any device running OS 10.2.1.1925 and later is patched from this vulnerability. This is really only an issue if you are on the same Wi-Fi network as an attacker but for now if you are connecting to public Wi-Fi hotspots I recommend disabling Wi-Fi file sharing at that time. The best solution is to simply download a newer OS version.
Check out the details on BlackBerry’s website