An issue was discovered in OnePlus One, X, 2, 3, 3T, and 5 devices with OxygenOS 5.0 and earlier. The attacker can reboot the device into the Qualcomm Emergency Download (EDL) mode through ADB or by using Volume-Up when connected to USB, which in turn could allow for downgrading partitions such as the Android Bootloader.

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.

An issue was discovered on OnePlus One, X, 2, 3, and 3T devices. Due to a lenient updater-script in the OnePlus OTA images, and the fact that both ROMs use the same OTA verification keys, attackers can install HydrogenOS over OxygenOS and vice versa, even on locked bootloaders, which allows for exploitation of vulnerabilities patched on one image but not on the other, in addition to expansion of the attack surface. 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 (on OnePlus 3/3T 'Secure Start-up' must be off).

An issue was discovered on OnePlus One, X, 2, 3, and 3T devices. OxygenOS and HydrogenOS are vulnerable to downgrade attacks. This is due to a lenient 'updater-script' in OTAs that does not check that the current version is lower than or equal to the given image's. Downgrades can occur even on locked bootloaders and without triggering a factory reset, allowing for exploitation of now-patched vulnerabilities with access to user data. This vulnerability can be exploited by a Man-in-the-Middle (MiTM) attacker targeting the update process. This is possible because the update transaction does not occur over TLS (CVE-2016-10370). In addition, a physical attacker can reboot the phone into recovery, and then use 'adb sideload' to push the OTA (on OnePlus 3/3T 'Secure Start-up' must be off).

An issue was discovered on OnePlus devices such as the 3T. The OnePlus OTA Updater pushes the signed-OTA image over HTTP without TLS. While it does not allow for installation of arbitrary OTAs (due to the digital signature), it unnecessarily increases the attack surface, and allows for remote exploitation of other vulnerabilities such as CVE-2017-5948, CVE-2017-8850, and CVE-2017-8851.

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.

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.