{
    "meta": {
        "title": "D-Central — ASIC Firmware Lock & Security Event Tracker",
        "description": "Event-driven registry of 4 ASIC firmware LOCK and security events (Bitmain + Braiins): signed-firmware/SSH lockdowns, Amlogic control-board locks, the Sept-2025 micro-USB port block and install-method changes — each with models affected, bypassability, current 2026 status, evidence grade and source. Plus a per-firmware lock-state summary (dev-fee ranges, lock-in, reversibility, install path).",
        "generated": "2026-07-18T06:18:32+00:00",
        "version": "1.0",
        "license": "https://creativecommons.org/licenses/by/4.0/",
        "license_name": "CC BY 4.0",
        "source": "https://d-central.tech/asic-firmware-lock-tracker/",
        "record_count": 4,
        "method": "EVENT-DRIVEN, not a changelog: only changes that alter what an owner can DO with their hardware (install/roll-back custom firmware, keep SSH, pay a dev fee) are recorded. Dev-fee figures are RANGES verified 2026-07 (BraiinsOS+ 2–2.5%, VNish 2–2.8%, LuxOS ~2.8%), never flat. Evidence grade: A = primary/vendor source, B = corroborated across independent installers, C = single/community source with an unverified detail. Uncertain dates/versions are flagged, never asserted.",
        "provenance": "Bitmain support docs, Braiins Academy, D-Central firmware update guide, independent install guides (millionminer, Altair Technology). No VNish-specific exploit content — VNish is described only at the neutral feature/dev-fee level.",
        "disclaimer": "Lock behavior changes with each firmware release and varies by control-board revision. The Sept-2025 port block is corroborated by installers but not confirmed against a primary Bitmain release note (grade C). The Amlogic SoC part number is cited inconsistently across sources (A113D vs A311D) and is left unverified. Verify against your specific board before unlocking; unlocking can brick a miner."
    },
    "events": [
        {
            "date": "2022-01",
            "vendor": "Bitmain",
            "event_type": "signed-firmware / SSH lock",
            "models": "S15, S17/S17+, S19/S19 Pro, Z11 — all 'Security Firmware' S-gen",
            "versions": "Bitmain 'Security Firmware' builds (rolled out ~2021; Q&A doc last updated 2022-01-30)",
            "what_changed": "Bitmain's Security Firmware added firmware-signature verification and DISABLED root SSH on the miner. Stated as anti-malware; the practical effect is that SSH — historically the on-ramp for flashing custom firmware — is gone on these builds.",
            "bypassable": "partial — custom firmware is still installable via Toolbox/SD on Zynq/BeagleBone boards; the SSH lock only removes the SSH install path, not every path on pre-Amlogic hardware.",
            "status_2026": "Baseline behavior on all modern stock firmware; SSH flashing is not the standard 2026 route. Superseded in importance by the Amlogic control-board locks below.",
            "evidence_grade": "A",
            "source": "Bitmain support: Antminer Security Firmwares Q&A"
        },
        {
            "date": "2024-03",
            "vendor": "Bitmain",
            "event_type": "secure-boot / control-board lock",
            "models": "S19k Pro, S21, T21, and late S19/S21 units on Amlogic control boards (2023+)",
            "versions": "Stock firmware on Amlogic control boards from March 2024 onward",
            "what_changed": "Bitmain began shipping Amlogic-based control boards (no SD slot; a micro-USB port instead) whose firmware blocks direct installation of BraiinsOS+, VNish or LuxOS. Third-party firmware can no longer be flashed straight onto these boards without unlocking them first.",
            "bypassable": "yes — via a third-party Amlogic unlock kit (~US$85) that uses the micro-USB/UART path to boot an older unlocked build, after which a normal Toolbox install proceeds (~45 min, 'Path B').",
            "status_2026": "Still the governing lock for boards on March-2024 through August-2025 firmware. Actively worked around in the field; this is the beginning of the control-board lock era.",
            "evidence_grade": "B",
            "source": "D-Central firmware update guide; millionminer install guide; Altair Technology"
        },
        {
            "date": "2025-09",
            "vendor": "Bitmain",
            "event_type": "port block (micro-USB)",
            "models": "Amlogic-control-board miners on Sept-2025+ stock firmware (S21-series, S19k Pro, T21 class)",
            "versions": "Bitmain stock firmware released September 2025 or newer (⚠ exact version string unverified)",
            "what_changed": "Bitmain shipped an update that disables/blocks the micro-USB port on Amlogic control boards — the exact port the unlock kit relies on. This closed the direct hardware-unlock path that had worked since the March-2024 locks. It is NOT an SSH-specific lockout and NOT new signed-firmware enforcement; it kills the physical micro-USB unlock on-ramp.",
            "bypassable": "partial — not directly. You must first downgrade stock firmware to the ~August-2025 pre-lock build via SD card, THEN apply the normal UART unlock. The unlock kit alone fails on post-Sept-2025 firmware (~2 hr, 'Path C').",
            "status_2026": "Still in effect as of mid-2026; the longest, riskiest install path. Custom firmware remains installable, just harder.",
            "evidence_grade": "C",
            "source": "millionminer install guide; Altair Technology — ⚠ corroborated by independent installers but NOT pinned to a primary Bitmain release note; date is month-only"
        },
        {
            "date": "2024",
            "vendor": "Braiins",
            "event_type": "install method (reversible)",
            "models": "Antminer S19/S21 series (Zynq/Xilinx, Amlogic, BeagleBone Black, Cvitek control boards)",
            "versions": "Braiins Toolbox (2026 build); BraiinsOS+",
            "what_changed": "Braiins Toolbox became the preferred install path, supporting remote batch installs across all common S19/S21 control-board families including Amlogic. SD-card install remains available for Zynq/BeagleBone and leaves internal NAND intact.",
            "bypassable": "n/a — this is an install method, not a lock. Included because reversibility is the counter-story to Bitmain's locks.",
            "status_2026": "Current standard install tooling. SD-card installs are fully reversible (remove the card and stock firmware boots with prior settings); NAND install is the permanent option.",
            "evidence_grade": "A",
            "source": "Braiins Academy — installation docs"
        }
    ],
    "firmware_lock_state": [
        {
            "name": "BraiinsOS+",
            "dev_fee": "2–2.5% range (verified 2026-07); effectively 0% when mining on Braiins Pool",
            "lock_in": "None — does not secure-boot the device against you; you can leave.",
            "reversibility": "Fully reversible. SD-card install leaves stock NAND intact; revert to Bitmain stock supported.",
            "install_2026": "Braiins Toolbox (preferred, remote batch) or SD card; on Mar-2024+ Amlogic boards needs an unlock first, and on Sept-2025+ firmware needs an SD downgrade to the Aug-2025 build, then unlock.",
            "open_source": "partial — much tooling and the BCB100 open-hardware path are open, but production ASIC-control binaries are closed. Do NOT claim 'fully open source'."
        },
        {
            "name": "VNish",
            "dev_fee": "2–2.8% range (verified 2026-07); charged on hashrate regardless of pool — no free/pool-tied tier",
            "lock_in": "Aftermarket firmware; adds no secure-boot lock-in beyond stock.",
            "reversibility": "Reversible to stock via standard reflash on unlocked boards.",
            "install_2026": "Web-UI / toolkit reflash on unlocked control boards; same Amlogic unlock prerequisites apply as for any custom firmware.",
            "open_source": "no — closed source (described here only at feature/dev-fee level)."
        },
        {
            "name": "LuxOS",
            "dev_fee": "~2.8% (verified 2026-07); waived when mining on Luxor Pool",
            "lock_in": "Aftermarket firmware; no added secure-boot lock-in.",
            "reversibility": "Reversible to stock on unlocked boards.",
            "install_2026": "Vendor tool/API reflash on unlocked control boards; same Amlogic unlock prerequisites apply.",
            "open_source": "no — closed source."
        },
        {
            "name": "DCENT_OS",
            "dev_fee": "0% (D-Central's own OS; sovereignty-first positioning)",
            "lock_in": "No user lock-in by design; no secure-boot-against-owner.",
            "reversibility": "Reversible per open-firmware norms.",
            "install_2026": "Via the /flash/ web flasher and DCENT tooling; subject to the same underlying Bitmain Amlogic unlock prerequisites on locked hardware.",
            "open_source": "yes — public beta, GPL-3.0."
        },
        {
            "name": "Bitmain stock",
            "dev_fee": "0% (no dev fee; monetized via hardware + optional pool)",
            "lock_in": "LOCKS YOU IN on Amlogic boards — signed firmware + disabled SSH (2022), escalated to control-board firmware locks (Mar 2024) and a micro-USB port block (Sept 2025).",
            "reversibility": "Anti-downgrade enforced on newer builds; an SD-card downgrade to a pre-lock build is the field workaround where hardware permits.",
            "install_2026": "Ships stock; official updates via web UI/SD. Removing it for custom firmware now requires unlock steps that scale with firmware age.",
            "open_source": "no — closed source."
        },
        {
            "name": "MicroBT (Whatsminer) stock",
            "dev_fee": "0% (no dev fee)",
            "lock_in": "Historically more permissive than Bitmain for third-party firmware, but no first-class custom-firmware ecosystem equivalent to Antminer's.",
            "reversibility": "Vendor-controlled; not the focus of the 2024/2025 Bitmain lock events.",
            "install_2026": "Stock via WhatsMinerTool; custom-firmware support is narrower than Antminer.",
            "open_source": "no — closed source."
        }
    ]
}