The Walton Primo G3 Android device with a build fingerprint of WALTON/Primo_GM3/Primo_GM3:8.1.0/O11019/1522737198:user/release-keys contains a pre-installed app with a package name of com.mediatek.wfo.impl app (versionCode=27, versionName=8.1.0) that allows any app co-located on the device to modify a system property through an exported interface without proper authorization.