RT-AX5400

- Enhanced system stability.
- Enhanced input validation and refactored legacy string handling routines to ensure robust memory management.
- Mitigated security risks in AiCloud service by enforcing strict credential verification, implementing robust file path validation, and hardening command execution logic to prevent unauthorized access and manipulation of system resources.
- Implemented comprehensive validation and expanded command filtering in the web history API.
- Strengthened input validation and directory handling in the VPN configuration upload interface.
- Fixed an issue that allowed certain user settings to be bypassed, improving overall user control and protection.

Important: After installing this firmware, we strongly recommend performing a factory-default reset to activate every new security adjustment.

Security Enhancements
- Password Policy Upgrade – Minimum 10 characters with at least 1 letter, 1 digit and 1 special symbol, and no consecutive identical characters; hardens defense against brute-force attacks.
- HTTPS on 8443 – Management interface now served over TLS by default.
- UPnP Disabled – Universal Plug and Play starts in the off state for reduced surface exposure.
- AiCloud Authentication Hardening (CWE-287) – Added layered verification.
- Authentication Logic Refactor – Removed redundant code paths for a lean sign-in flow.
- Memory Safety Guard (CWE-476) – Introduced null-reference protections across critical services.
- Enhanced IPsec Parameter Validation – The existing input checks have been hardened
- Data Exposure Mitigation (CWE-200) – Reinforced controls on sensitive pathways.
- Detailed Audit Trails – Expanded logging within the authentication module.

System Improvements
- Connection Stability – Core algorithms refined for steadier links.
- Scheduling Accuracy – Timed tasks execute reliably under PPPoE, PPTP and L2TP WAN modes.
- Client List Maintenance – Resolved an issue that prevented offline devices from being removed from the client list.

Bug Fixes:
- Fixed abnormal client list.
- Fixed abnormal GUI behavior of Wireguard VPN.
- Fixed USB internet backup conflict with main WAN.
- Fixed abnormal WAN detection while AiDetection is enabled.
- Improved AdGuard DNS GUI issues.
- Fixed IPv6 related issues.
- Improved USB tether compatibility for pixel phones.

Improved compatibility with certain IoT devices.

1.Enhanced input parameter handling techniques to improve data processing stability and system security.
2.Enhance system access control mechanisms.

1.Fixed the UI issue in Chrome.
2.Fixed client binding issues in Mesh scenarios.

Please unzip the firmware file, and then verify the checksum.
SHA256: 263ba5196f9b5d8cf0dcdc5e79051aa338fe0d23a681bc326d30ce38bf34792f

Improved the ability to modify the HTTPS port in AP mode via the web UI.

1. Strengthened input validation and data processing workflows to further protect information security.
2. Enhanced AiCloud password protection mechanisms, safeguarding against unauthorized access attempts.
3. Enhanced device security through improved buffer handling in connection features.
4. Refined data handling processes, ensuring secure and accurate information management.
5. Enhanced file access control mechanisms, promoting a more secure operating environment.
6. Strengthened certificate protection, providing enhanced data security.

Please unzip the firmware file, and then verify the checksum.
SHA256: 1cc7d3206cfbd89a54a099a973d9c44a279b55144c7bd97f25d99445ade19e7d

1. Strengthened system code execution processes.
2. Enhanced AiCloud password protection mechanisms, safeguarding against unauthorized access attempts.
3. Refined input validation in the web interface, ensuring a more secure web interaction environment.
4. Improved data export functionality in the admin portal, ensuring accurate and secure handling of client information.
5. Optimized memory management mechanisms, improving system stability.
6. Improved system buffer management, ensuring reliable data processing workflows.
7. Enhanced stack buffer management, promoting greater system stability.

Please unzip the firmware file, and then verify the checksum.
SHA256: d155df280e4e64cea5efef8468a6b9eeec6038fd73f0ee73a2cea1c4ee0ec694