Huawei P9 versions earlier before EVA-AL10C00B373, versions earlier before EVA-CL00C92B373, versions earlier before EVA-DL00C17B373, versions earlier before EVA-TL00C01B373 have a lock-screen bypass vulnerability. An unauthenticated attacker could force the phone to the fastboot mode and delete the user's password file during the reboot process, then login the phone without screen lock password after reboot.