Before discussing the flaw, we must understand the target. The MediaTek MT6789 is a system-on-a-chip (SoC) fabricated on a 6nm process. It is the successor to the Helio G90 series and is found in volume-brand devices such as:
The MT6789 supports up to 108MP cameras, 120Hz displays, and 4G LTE. Critically, it implements Bootrom-level security—a fused, immutable layer of code that runs before any other software.
Even if the SLA passes, the DA itself (the binary that runs on the SoC to read/write flash) must be signed with MediaTek's private key. DAA ensures that only authorized, unmodified MediaTek agents can execute. mt6789 auth bypass
Together, SLA & DAA make traditional "unbricking" or forensic imaging impossible without the manufacturer’s proprietary authentication file (usually an auth_sv5.auth file tied to a specific device or project).
The dark side: An attacker with physical access can use the MT6789 auth bypass to install persistent rootkits directly into the boot partition (or even the vendor’s lk.bin – little kernel). Because the exploit operates at the BootROM level, it survives factory resets and OS reinstallation. A compromised Preloader could theoretically exfiltrate data via USB even when the device is "powered off." Before discussing the flaw, we must understand the target
The MT6789 auth bypass is a reminder that no silicon is perfect. MediaTek’s recovery strategy involves moving authentication into the TEE (TrustZone) where the BootROM simply loads a small, verified "mini-loader" that then enforces SLA/DAA in software. This would allow OTA patches for future auth bypasses.
However, for millions of MT6789 devices already in circulation, the vulnerability is permanent. From a forensics perspective, this chipset has become the "golden bullet" – enabling full physical extraction on budget and mid-range Android phones previously considered secure. The MT6789 supports up to 108MP cameras, 120Hz
To appreciate the bypass, you must understand what it circumvents:
The Preloader is a small, proprietary boot stage stored in the chip’s internal ROM or masked in the BootROM. It handles initial hardware initialization and listens to the USB port for a "handshake" from a host PC running tools like SP Flash Tool or MTK Client.