On TCL Alcatel Cingular Flip 2 B9HUAH1 devices, PIN authentication can be bypassed by creating a special file within the /data/local/tmp/ directory. The System application that implements the lock screen checks for the existence of a specific file and disables PIN authentication if it exists. This file would typically be created via Android Debug Bridge (adb) over USB.
alcatelmobile
CVE-2019-16242
On TCL Alcatel Cingular Flip 2 B9HUAH1 devices, there is an engineering application named omamock that is vulnerable to OS command injection. An attacker with physical access to the device can abuse this vulnerability to execute arbitrary OS commands as the root user via the application’s UI.
CVE-2019-16243
On TCL Alcatel Cingular Flip 2 B9HUAH1 devices, there is an undocumented web API that allows unprivileged JavaScript, including JavaScript running within the KaiOS browser, to view and edit the device’s firmware over-the-air update settings. (This web API is normally used by the system application to trigger firmware updates via OmaService.js.)