CVE-2025-3988 is a critical buffer overflow vulnerability identified in the TOTOLINK N150RT router, specifically version 3.4.0-B20190525. The flaw exists in an unspecified function within the /boafrm/formPortFw file, where improper handling of the 'service_type' argument allows an attacker to overflow a buffer. This vulnerability can be exploited remotely without requiring user interaction or prior authentication, as indicated by the CVSS vector (AV:N/AC:L/AT:N/UI:N/PR:L). The buffer overflow can lead to arbitrary code execution or cause the device to crash, impacting confidentiality, integrity, and availability of the affected device. The CVSS 4.0 base score is 8.7, categorized as high severity, reflecting the ease of exploitation and the significant impact on the device's security posture. Although no known exploits are currently reported in the wild, the public disclosure of the exploit code increases the risk of imminent attacks. The vulnerability affects a specific firmware version, and no official patches have been linked yet. TOTOLINK N150RT is a low-cost consumer-grade wireless router commonly used in small offices and home environments, often deployed in network edge positions, making it a potential entry point for attackers targeting internal networks.

For European organizations, the exploitation of this vulnerability could lead to unauthorized remote code execution on affected routers, enabling attackers to intercept, manipulate, or disrupt network traffic. This can compromise the confidentiality of sensitive communications, integrity of data passing through the device, and availability of network services. Small and medium enterprises (SMEs) and home offices using TOTOLINK N150RT routers are particularly at risk, as these devices often lack advanced security monitoring and are less likely to be promptly updated. Attackers could leverage compromised routers to establish persistent footholds, launch lateral movement within corporate networks, or conduct man-in-the-middle attacks. The disruption of network availability could also impact business continuity. Given the router’s role at the network perimeter, successful exploitation could undermine broader organizational cybersecurity defenses.

1. Immediate inventory and identification of all TOTOLINK N150RT devices running firmware version 3.4.0-B20190525 within the network environment. 2. Isolate affected devices from critical network segments until a patch or firmware update is available. 3. Monitor network traffic for unusual patterns indicative of exploitation attempts, such as unexpected requests to /boafrm/formPortFw or abnormal service_type parameter usage. 4. Implement network-level access controls to restrict remote access to router management interfaces, preferably limiting access to trusted IP addresses or VPN connections. 5. Employ intrusion detection/prevention systems (IDS/IPS) with updated signatures to detect attempts exploiting this vulnerability. 6. Engage with TOTOLINK support channels to obtain official patches or firmware updates and apply them promptly once available. 7. As a temporary workaround, disable remote management features if enabled, reducing the attack surface. 8. Educate IT staff and users about the risks associated with this vulnerability and the importance of timely updates and network hygiene.