CVE-2025-4442 is a critical buffer overflow vulnerability identified in the D-Link DIR-605L router, specifically version 2.13B01. The flaw exists in the function formSetWAN_Wizard55, where improper handling of the argument 'curTime' allows an attacker to cause a buffer overflow. This vulnerability can be exploited remotely without requiring user interaction or prior authentication, making it particularly dangerous. The buffer overflow can lead to arbitrary code execution, potentially allowing an attacker to take full control of the affected device. The vulnerability affects only devices running the specified firmware version, which are no longer supported by the vendor, meaning no official patches or updates are available. The CVSS 4.0 score is 8.7, indicating a high severity level with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the ease of exploitation and critical impact make this a significant threat. The lack of vendor support further exacerbates the risk as affected devices remain vulnerable indefinitely unless mitigated by other means.

For European organizations, this vulnerability poses a substantial risk, especially for those still operating legacy network infrastructure with the D-Link DIR-605L router running the vulnerable firmware. Successful exploitation could lead to complete compromise of the router, enabling attackers to intercept, modify, or disrupt network traffic, launch further attacks within the internal network, or use the device as a foothold for persistent access. This could impact confidentiality by exposing sensitive data, integrity by allowing unauthorized changes to network configurations or data, and availability by causing denial of service. Critical infrastructure, small and medium enterprises, and home office environments relying on these routers are particularly at risk. The absence of vendor patches means organizations must rely on network segmentation, device replacement, or other compensating controls to mitigate exposure. Given the router's typical deployment in smaller networks, the threat could also affect remote workers and branch offices, increasing the attack surface for larger organizations.

Since no official patches are available due to the product being out of support, European organizations should prioritize the following mitigations: 1) Immediate identification and inventory of all D-Link DIR-605L devices running firmware 2.13B01 or earlier. 2) Replacement of affected routers with supported models that receive regular security updates. 3) If replacement is not immediately feasible, isolate vulnerable devices on segmented network zones with strict firewall rules to limit inbound and outbound traffic, especially blocking WAN access to the router's management interfaces. 4) Disable any unnecessary services and remote management features on the affected routers to reduce attack vectors. 5) Monitor network traffic for unusual activity indicative of exploitation attempts, such as unexpected connections or anomalous payloads targeting the formSetWAN_Wizard55 function. 6) Implement network intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics capable of detecting exploitation attempts. 7) Educate IT staff and users about the risks and signs of compromise related to this vulnerability. 8) Maintain robust backup and incident response plans to quickly recover from potential breaches.