Since a security patch is the primary cause of Step 3 failures, the most definitive fix is flashing an older factory firmware image.
If you are running the tool manually via ADB, ensure it has executable permissions. Running a binary without proper access causes quick environment initialization drops. How to Fix "mtk-su failed critical init step 3" mtk-su failed critical init step 3
The mtk-su tool has seen many iterations. Using an older version on a newer kernel—or a newer version on a very old device—can cause initialization issues. Since a security patch is the primary cause
Have you managed to get past step 3 on a patched device? Share your experience in the comments or on XDA Developers—the community always benefits from new discovery. How to Fix "mtk-su failed critical init step
adb push mtk-su /data/local/tmp/ adb shell cd /data/local/tmp/ chmod 755 mtk-su ./mtk-su Use code with caution. 5. Alternative Rooting Methods (If All Else Fails)
Because mtk-su depends entirely on software vulnerabilities, you cannot simply force it to work if your system is securely patched. However, you can verify your configuration and test alternative entry points. Check Your File Permissions