An issue was discovered on OnePlus One and X devices. Due to a lenient updater-script on the OnePlus One and X OTA images, the fact that both products use the same OTA verification keys, and the fact that both products share the same 'ro.build.product' system property, attackers can install OTAs of one product over the other, even on locked bootloaders. That could theoretically allow for exploitation of vulnerabilities patched on one image but not on the other, in addition to expansion of the attack surface. Moreover, the vulnerability may result in having the device unusable until a Factory Reset is performed. This vulnerability can be exploited by Man-in-the-Middle (MiTM) attackers targeting the update process. This is possible because the update transaction does not occur over TLS (CVE-2016-10370). In addition, physical attackers can reboot the phone into recovery, and then use 'adb sideload' to push the OTA.

In OxygenOS before 4.0.3 on OnePlus 3 and 3T devices, an unauthorized attacker can cause a locked bootloader to partially dump the ciphertext content of an arbitrary partition (except 'keystore') by issuing the 'fastboot oem dump <partition>' fastboot command.

The SPDY/2 codec in Facebook Proxygen before 2015-11-09 truncates a certain field to two bytes, which allows hijacking and injection attacks.

Facebook Proxygen before 2015-11-09 mismanages HTTPMessage.request state, which allows remote attackers to conduct hijacking attacks and bypass ACL checks.

The SPDY/2 codec in Facebook Proxygen before 2015-11-09 allows remote attackers to conduct hijacking attacks and bypass ACL checks via a crafted host value.

With OxygenOS before 4.0.3, when a charger is connected to a powered-off OnePlus 3 or 3T device, the platform starts with adbd enabled. Therefore, a malicious charger or a physical attacker can open up, without authorization, an ADB session with the device, in order to further exploit other vulnerabilities and/or exfiltrate sensitive information.

An issue was discovered in OxygenOS before 4.1.0 on OnePlus 3 and 3T devices. The attacker can change the bootmode of the device by issuing the 'fastboot oem boot_mode {rf/wlan/ftm/normal} command' in contradiction to the threat model of Android where the bootloader MUST NOT allow any security-sensitive operation to be run unless the bootloader is unlocked.

An issue was discovered in OxygenOS before 4.0.3 for OnePlus 3 and 3T. The attacker can persistently make the (locked) bootloader start the platform with dm-verity disabled, by issuing the 'fastboot oem disable_dm_verity' command. Having dm-verity disabled, the kernel will not verify the system partition (and any other dm-verity protected partition), which may allow for persistent code execution and privilege escalation.

OxygenOS before version 4.0.2, on OnePlus 3 and 3T, has two hidden fastboot oem commands (4F500301 and 4F500302) that allow the attacker to lock/unlock the bootloader, disregarding the 'OEM Unlocking' checkbox, without user confirmation and without a factory reset. This allows for persistent code execution with high privileges (kernel/root) with complete access to user data.

An issue was discovered in ABOOT in OnePlus 3 and 3T OxygenOS before 4.0.2. The attacker can reboot the device into the fastboot mode, which could be done without any authentication. A physical attacker can press the "Volume Up" button during device boot, where an attacker with ADB access can issue the adb reboot bootloader command. Then, the attacker can put the platform's SELinux in permissive mode, which severely weakens it, by issuing: fastboot oem selinux permissive.