The Lava Z60s Android device with a build fingerprint of LAVA/Z60s/Z60s:8.1.0/O11019/1530331229: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.