Various mods for the Sony Xperia Z2 are starting to show up, but most, if not all, of them require unlocked bootloaders. But if you only want to get your device rooted, you can now actually do so, even without an unlocked bootloader. The process, however, might not be for the faint of heart.
Flashing a recovery, installing CyanogenMod, or even the process of rooting itself all start with an unlocked bootloader. While Sony has provided official ways to unlock the bootloaders of dozens of their devices, there has so far been no movement when it comes to the Xperia Z2 or the Xperia Z2 tablet. For those itching to get super user access on their smartphones, there is now a way to do so courtesy of XDA developers such as DooMLoRD and company. However, the process isn't as simple as Sony's steps and require a bit of work.
In essence, like many rooting procedures, the steps exploit vulnerabilities in the software in order to gain root access. This one, however, has more steps involved and requires a computer, desktop or laptop, running Windows and a USB connection. While there is a script involved to automate most of the process, manual intervention is still required in many of the parts. If you do manage to survive the ordeal, you will be rewarded with a rooted device that still has a locked bootloader.
That said, there is one caveat to this already straining process. It will only work older Xperia Z2 firmware, specifically those with build numbers 17.1.A.2.55 and 17.1.A.2.69. The exploit that is being used in this process has already been patched up in the latest 17.1.1.A.0.402, making it entirely useless. Hopefully, Sony will put out instructions for the Xperia Z2 and Xperia Z2 Tablet soon to spare their users from having to resort to such methods.
VIA: Xperia Blog