CVE-2025-6128 is a critical buffer overflow vulnerability identified in the TOTOLINK EX1200T router, specifically version 4.1.2cu.5232_B20210713. The flaw resides in the HTTP POST request handler component, within the /boafrm/formWirelessTbl endpoint. The vulnerability is triggered by manipulating the 'submit-url' argument in the POST request, which leads to a buffer overflow condition. This type of vulnerability can allow an attacker to overwrite memory, potentially resulting in arbitrary code execution, denial of service, or system compromise. The vulnerability is remotely exploitable without requiring authentication or user interaction, increasing the risk profile. The CVSS 4.0 base score is 8.7 (high severity), reflecting the network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (VC:H/VI:H/VA:H). Although no known exploits are currently observed in the wild, the public disclosure of the exploit code increases the likelihood of active exploitation attempts. The vulnerability affects a widely deployed consumer and small office/home office (SOHO) router model, which is commonly used to provide wireless connectivity. Given the criticality and ease of exploitation, attackers could leverage this flaw to gain control over affected devices, pivot into internal networks, intercept or manipulate traffic, or disrupt network availability.

For European organizations, especially small and medium enterprises (SMEs) and home users relying on TOTOLINK EX1200T routers, this vulnerability poses a significant risk. Exploitation could lead to unauthorized access to internal networks, data interception, or disruption of network services. This is particularly concerning for organizations with limited IT security resources that may not promptly patch or replace vulnerable devices. Critical infrastructure providers or businesses with remote workforces using these routers could face increased exposure to espionage, data breaches, or operational downtime. The compromise of these routers could also serve as a foothold for lateral movement within corporate networks or as a launchpad for broader attacks. Given the lack of authentication and user interaction requirements, attackers can automate exploitation at scale, increasing the threat to European networks. Additionally, the absence of an official patch or mitigation from the vendor at the time of disclosure exacerbates the risk.

1. Immediate network segmentation: Isolate TOTOLINK EX1200T devices from critical internal networks to limit potential lateral movement if compromised. 2. Disable remote management interfaces on the router to reduce exposure to external attacks. 3. Monitor network traffic for unusual POST requests targeting /boafrm/formWirelessTbl or anomalous patterns indicative of exploitation attempts. 4. Replace or upgrade affected devices to models with confirmed security patches or from vendors with robust security update policies. 5. Implement strict firewall rules to restrict inbound traffic to router management interfaces, allowing only trusted IP addresses if remote access is necessary. 6. Employ intrusion detection/prevention systems (IDS/IPS) with signatures tuned to detect exploitation attempts targeting this vulnerability. 7. Educate users and administrators about the risks and signs of router compromise, including unexpected device behavior or network disruptions. 8. Regularly audit and update router firmware, and subscribe to vendor security advisories for timely patch releases. Since no official patch is currently available, these compensating controls are critical to reduce risk until a fix is released.