You can find the download link of ZTE S518 Stock Firmware ROM (flash file) on this page. The Stock Firmware comes in a zip package that contains the original Firmware, Flash Tool, Driver, and How-to Flash manual.
You can use the ZTE firmware to Upgrade or Downgrade the Operating System (OS) of the device, Unlock or remove the device’s protection, Fix the IMEI-related issue, or Fix the bootloop problem.
File Name: ZTE_S518_MT6252_S01.CLL-ZA-QD-P110A19V1_0_0B03_30072017_MIRA.zip
File Size: 2 MB
Flash Tool: Miracle Tool
How-to Flash (install): Use Miracle Tool to Flash this firmware.
[*] Flash Tool: If you are looking for the latest version of Miracle Tool, then head over to Miracle Tool page.
[*] Backup: We recommend taking a backup of your data before flashing or installing the Stock Firmware (ROM), as flashing the Firmware will wipe the data from the device.
[*] Original firmware: We only Serve the original firmware, which the device manufacturer releases, and we scan each of the firmware using MalwareBytes Premium before sharing it online.