Warning: Using leaked Firehose loaders on modern Samsung (binary 4+) can permanently fuse the device into "900E" mode (hard brick).
After writing the changes, you issue edl reset. The device reboots. The Knox counter may be tripped (0x1), and Samsung Pay/Warranty is void, but the MDM lock is gone.
Even if successful, MDM locks can re-appear after:
The tool reads the raw partition table (GPT). You look for specific partitions:
Before we discuss unlocking, we must understand how Samsung implements MDM. Unlike Google's basic Factory Reset Protection (FRP), Samsung uses Knox Guard.
When a company enrolls a device into MDM (e.g., via Knox Mobile Enrollment), a hardware-level e-fuse is tripped, and a secure token is written to the device’s persistent partition. This token survives:
The MDM lock is stored in the CID (Consumer ID) or the Persistent Data Block, which is not wiped by standard user tools. This is where EDL Mode comes in.
Connect via Tool – The MDM unlock tool (e.g., Samsung MDM Bypass Tool, UnlockTool, Octoplus Box, Z3X, or free scripts) connects to the device in EDL mode over USB.
Execute Bypass – The tool sends custom Qualcomm Sahara/Firehose loaders to read/modify the persist partition or Knox flag data, effectively clearing the MDM enrollment flag.
Result – The device reboots without MDM restrictions, allowing normal setup.
Prerequisites:
The Process:
prog_emmc_firehose_Sm8xxx.bin file.