Orbit — firmware, direct from Samsung's FUS servers

Every Samsung firmware mirror is slow, shady, or both. Orbit cuts them out — it downloads firmware straight from Samsung's own FUS distribution servers, at full speed, with per-partition extraction so you only pull what you actually need.

• GPL-3.0 · release v2.1.0 · GUI (dark) + CLI
• downloads a single BL image in ~82 MB on the wire instead of a 21.6 GB bundle
• byte-identical results, verified against SamFw's copies

What was reverse-engineered

• The FUS protocol — modern SmartDownload + legacy paths, the auth_param.dat handshake (a custom block cipher), binary XML responses, and the download URL shape (cloud-neofussvr.samsungmobile.com/NF_DownloadBinaryForMass.do).
• zip64 range extraction — firmware bundles are encrypted zip64 containers. Orbit downloads per-partition ranges and verifies every byte (CRC32 / md5 / sha256).
• The catalogue — all released builds per model (SamFrew endpoints), CP auto-resolution, the factory channel, and a CSC browser.

Features

• segmented downloads with pause / resume / cancel
• per-partition extraction (grab just the BL, just the CP, whatever)
• full hash verification on every file
• phone auto-detect via adb — model + sales code → auto-check for the newest build
• download history, in-app guides, factory firmware channel
• GUI + CLI, both dark

Usage

bash

GUI

orbit # or: python fusclient.py --gui

CLI — check the newest firmware for a model/region

fusclient -m SM-F956B -r XSA check

CLI — list available versions

fusclient -m SM-F956B -r XSA list

CLI — browse every released build (SamFrew catalogue)

fusclient -m SM-F956B -r XSA catalogue

CLI — pull just the bootloader (per-part extraction, ~82 MB on the wire)

fusclient -m SM-F956B -r XSA download --parts BL -o firmware/

verify what you pulled (sha256 + Samsung .tar.md5 trailer)

fusclient verify ./F956BXXS4DZI1_BL.tar.md5 ``````

Why it matters

Orbit gave us the verified DZI1 flash set (hashes in dumps-hashes/) used for the Track A downgrade attempt and every recovery flash since — and the per-part range trick is the cheap way to pull single boot-chain images for reverse engineering.

Credit & lineage

Orbit reimplements Samsung's FUS protocol from public GPL-3.0 reference code — nothing copied, everything verified byte-for-byte against the same servers:

• samloader (c) 2020 nlscc — the original FUS downloader + auth_param scheme.
• Bifrost (c) Zachary Wander — the modern SmartDownload flow; auth_param.dat is bundled from Bifrost with attribution.
• SamFrew — the release-catalogue endpoints (every build ever released per model).

Fine print

Downloads are for your own device, in regions where Samsung distributes them. No Samsung property is bundled or redistributed — Orbit just talks to the same servers your phone's own updater talks to.