CVE-2025-11294 is a remote buffer overflow vulnerability identified in the Belkin F9K1015 router firmware version 1.00.10. The flaw exists in the handling of the L2TPUserName argument within the /goform/formL2TPSetup endpoint, which is part of the router's web management interface. By sending a specially crafted request to this endpoint, an attacker can overflow a buffer, potentially overwriting memory and gaining control over the device's execution flow. The vulnerability requires no authentication or user interaction, making it remotely exploitable over the network. The CVSS 4.0 score of 8.7 reflects its high severity, with low attack complexity and no privileges required. The vulnerability impacts confidentiality, integrity, and availability by enabling remote code execution, which could allow attackers to intercept traffic, alter configurations, or disrupt network services. Despite early disclosure, Belkin has not responded or released a patch, and a public exploit is available, increasing the likelihood of exploitation. The affected device is commonly used in small to medium business and home environments, often with exposed WAN interfaces or weak perimeter defenses. This vulnerability underscores the risks of unpatched embedded devices in network infrastructure.

For European organizations, the impact of CVE-2025-11294 can be significant. Compromise of Belkin F9K1015 routers could lead to unauthorized access to internal networks, interception of sensitive communications, and disruption of business operations. Critical infrastructure sectors relying on these devices for VPN or remote access could face operational outages or data breaches. The lack of vendor response and patch availability increases exposure time, making exploitation more probable. Organizations with remote management enabled or insufficient network segmentation are particularly vulnerable. The potential for remote code execution means attackers could establish persistent footholds, pivot within networks, or launch further attacks against connected systems. This vulnerability also raises concerns about supply chain security and the need for rigorous device management policies in European enterprises.

Given the absence of an official patch, European organizations should implement immediate compensating controls. First, restrict access to the router's management interface by limiting inbound connections via firewall rules to trusted IP addresses only. Disable L2TP or related VPN services on the device if not in use. Employ network segmentation to isolate vulnerable routers from critical assets. Monitor network traffic for anomalous requests targeting /goform/formL2TPSetup or unusual L2TPUserName parameter patterns. Consider replacing affected devices with models from vendors that provide timely security updates. Where replacement is not feasible, deploy intrusion prevention systems (IPS) with signatures targeting this exploit. Regularly audit device firmware versions and maintain an inventory of network equipment to identify at-risk devices. Finally, educate IT staff about the vulnerability and the importance of rapid incident response in case of suspected exploitation.