With Sony's efforts to support the Android modding and developer community, it really should come as no surprise that the recently-unveiled Xperia Z smartphone is now bestowed with root. The noteworthy achievement is facilitated by the CF-Auto-Root solution available for the LG-made Google Nexus 4, a device which shares most of the underpinnings of the Xperia Z.
The two devices share the same 1.5GHz quad-core Qualcomm Snapdragon S4 Pro chipset and because of it the developer has only slightly modified the Nexus 4 ramdisk from CF-Auto-Root to unleash elevated privileges on the Xperia Z. The app chosen to manage rooting requests is the traditional SuperSU.
The Xperia Z must sport an unlocked bootloder in order to enable root, as well as firmware version 10.1.A.1.350. The fastboot tool is also needed as to upload files onto the device. Users have to reboot into bootloader mode, flash a modded kernel, reboot, disconnect the USB cable and perform a hard shut down, before reconnecting the Xperia Z in fastboot mode, flashing the stock kernel and rebooting the device.
In order to fully take advantage of apps that require root it is also recommended to install a BusyBox from Google Play. BusyBox by Stephen (Stericson) comes highly recommended by members of the modding community. The app installs a number of files (the recommended path to install them is /system/xbin/) which can be used by apps that require elevated privileges to run certain commands.
The root method has been tested on an Xperia Z model C6603, but according to the developer it should work on the C6602 variant as well.