CVE-2025-53754 is a medium-severity vulnerability identified in the Digisol XPON ONU Wi-Fi Router model DG-GR6821AC, specifically affecting firmware version V3.2.XX. The root cause of this vulnerability is the presence of hard-coded root access credentials embedded within the device's firmware configuration. These credentials are static and cannot be changed by the end user, which violates secure coding practices as outlined in CWE-798 (Use of Hard-coded Credentials). An attacker with physical access to the device can extract the firmware binary, analyze it offline, and retrieve these embedded root credentials. Possession of these credentials grants the attacker administrative privileges on the router, enabling full control over the device. This could allow unauthorized configuration changes, interception or redirection of network traffic, installation of persistent malware, or use of the device as a pivot point for further network compromise. The CVSS 4.0 base score is 5.1, reflecting a medium severity level. The vector indicates the attack requires physical access (AV:P), but no authentication or user interaction is needed once access is obtained. The vulnerability does not impact confidentiality, integrity, or availability remotely but poses a significant risk if an attacker can physically access the device or its firmware. No known exploits are currently reported in the wild, and no patches have been released yet by the vendor. This vulnerability highlights the risks associated with embedded devices that rely on static credentials, especially in environments where physical security cannot be guaranteed.

For European organizations, the impact of this vulnerability depends largely on the deployment context of the Digisol DG-GR6821AC routers. Organizations using these routers in office or branch environments with limited physical security controls could face significant risks. An attacker gaining physical access to the device could compromise network integrity and confidentiality by manipulating router settings or intercepting internal communications. This is particularly concerning for sectors handling sensitive data such as finance, healthcare, or government agencies. Additionally, compromised routers could be leveraged as entry points for lateral movement within corporate networks, increasing the risk of broader intrusions. The lack of remote exploitation reduces the risk for organizations with strong physical security, but environments with publicly accessible or poorly secured network equipment remain vulnerable. The absence of patches means organizations must rely on compensating controls until a fix is available. Overall, the vulnerability could lead to unauthorized administrative access, network disruption, data leakage, and potential regulatory compliance issues under GDPR if personal data is exposed.

1. Physical Security: Strengthen physical security controls around network infrastructure to prevent unauthorized access to routers. This includes locked server rooms, restricted access areas, and surveillance. 2. Device Inventory and Replacement: Identify all deployed Digisol DG-GR6821AC routers running vulnerable firmware and plan for their replacement or isolation if possible. 3. Firmware Analysis and Customization: If feasible, extract and analyze firmware to identify hard-coded credentials and attempt to re-flash devices with customized firmware versions that remove or change these credentials. 4. Network Segmentation: Isolate vulnerable devices on separate network segments with strict access controls to limit potential lateral movement in case of compromise. 5. Monitoring and Logging: Implement enhanced monitoring for unusual administrative access attempts or configuration changes on these routers. 6. Vendor Engagement: Engage with Digisol for timely patch releases or firmware updates addressing this vulnerability. 7. Incident Response Preparedness: Prepare incident response plans specifically addressing scenarios involving physical compromise of network devices. 8. Disable Unused Services: Where possible, disable unnecessary services or interfaces on the router to reduce attack surface. These steps go beyond generic advice by focusing on physical security, device lifecycle management, and network architecture adjustments tailored to this vulnerability's characteristics.