To change the Master Code or User Codes on an AEI DK-9830 digital keypad, follow these steps according to the AEI DK-9830 User Manual How to Change the Master Code

The Master Code is used only to enter programming mode; it cannot be used to operate the door. The factory default is Enter the existing Master Code twice: [Master Code] [Master Code]

(The status LED should turn amber/orange, indicating programming mode). (to select the Master Code location). Enter your new 4-digit Master Code to confirm. to exit programming mode. How to Change or Add a User Code

User Codes are stored in memory "slots" (01 to 20 for this model). Master Code twice to enter programming mode. 2-digit Slot Number for the first user). Enter your new 4-digit User Code to confirm. Repeat steps 2–4 for other users, or press Reset to Factory Defaults

2. Assumptions & Threat Model

• Assumed environment: Local admin, remote management via HTTPS/SSH, optional physical access.
• Adversaries: Network eavesdropper, active MITM, remote attacker with valid session token, local attacker with filesystem access, privileged insider, side-channel attacker.
• Trust anchors: Device boot integrity, device certificate store, secure clock (or monotonic counter).

10. Recovery & Reset Procedures

• Secure factory-reset procedure that requires physical presence (button press with power-cycle) or authenticated recovery token printed on device provisioning label.
• Emergency admin reset: require signed reset request using device-specific attestation; log event and force password change on next boot.

8. Rate Limiting & Lockout

• Per-account exponential backoff and temporary lockout after configurable failed attempts (e.g., 5 attempts → 30s, 6→2m, 7→15m). Persist failed-attempt counters in non-volatile storage with decay.

Part 2: How to Change the Password on AEI DK 9830 (Standard Method)

If you already know the current administrator password and simply want to update it for security, follow these steps:

Step 1: Log into Admin mode as described above.

Step 2: Navigate to System Settings (usually using the up/down arrows). Press OK.

Step 3: Scroll down to Admin Options or Security Settings.

Step 4: Select Change Admin Password (sometimes labeled as "PWD Management").

Step 5: You will be prompted to enter the Old Password. Type it in and press OK.

Step 6: Enter the New Password.

• Best Practice: Use a 6-8 digit number. Do not use sequential numbers (123456) or repeated numbers (111111).
• Avoid: Birthdays or the company room number.

Step 7: Confirm the New Password by typing it again.

Step 8: The machine will beep and display: "Password changed successfully."

Step 9: Press ESC to return to the main screen. Log out by pressing Menu again or simply waiting 10 seconds. Test the new password immediately.

Pro Tip: Write the new password down in a sealed envelope stored in a company safe. Do not tape it to the back of the machine.

Step 7: Exit and Test

• Press the Menu or Esc key repeatedly to exit all menus and return to the standby screen.
• Log out entirely (if the device doesn’t auto-logout, remove your fingerprint or wait 10 seconds).
• Test your new password by re-entering the menu using the newly created credentials. This is critical—never lock yourself out without a backup.

Troubleshooting Common Password Change Issues

| Problem | Possible Cause | Solution | | :--- | :--- | :--- | | "Access Denied" when entering menu | Incorrect current password | Ensure caps lock is off (not relevant for digits); check if someone changed default; try 0000. | | New password not accepted | Too short/long or contains invalid character | Use strictly 4-8 numeric digits; no letters or symbols. | | Device freezes after saving | Firmware glitch | Power cycle (unplug for 30 seconds). The new password should still be active. | | User password change not working | Insufficient admin privileges | Log in with master admin, not a sub-admin account. |

5.3 SSH/CLI Flow

• Use PAM or native auth module; password change performed by exec of secure utility that validates, updates, and logs.

5.1 API Endpoint (REST) — /api/v1/password/change

• Method: POST
• Auth: Bearer token tied to session; require re-authentication with current password for sensitive operation.
• Payload (JSON):
  • current_password: string (UTF-8)
  • new_password: string (UTF-8)
  • new_password_confirm: string (UTF-8)
  • nonce: base64 (32 bytes) — server-generated challenge included in form to tie to session
  • otp: optional string (for 2FA)
• Transport: TLS 1.3; server requires client to include Origin and CSRF token header when from web UI.
• Response: 200 OK or structured error codes (400/401/403/429/500). Use JSON with code and message.