The vulnerability identified as CVE-2025-63465 affects the Totolink LR350 router firmware version 9.3.5u.6369_B20220309. It is a stack overflow vulnerability triggered by a specially crafted request targeting the ssid parameter processed in the sub_422880 function. Stack overflow vulnerabilities occur when more data is written to a buffer than it can hold, overwriting adjacent memory and potentially causing the program to crash or behave unpredictably. In this case, the overflow leads to a denial of service (DoS) condition, crashing the router and disrupting network connectivity. The vulnerability does not require any authentication or user interaction, making it easier for remote attackers to exploit. No CVSS score has been assigned yet, and no patches or known exploits have been reported at the time of publication. The affected device, Totolink LR350, is a widely used wireless router model, often deployed in home and small business networks. The flaw could be exploited remotely by sending maliciously crafted requests to the router’s management interface or wireless service, causing service interruptions. This vulnerability primarily impacts availability, as it results in device crashes and network downtime. The absence of authentication requirements increases the risk profile, as attackers do not need credentials to launch the attack. While no direct integrity or confidentiality compromise is indicated, the DoS effect can severely disrupt network operations.

For European organizations, the primary impact of CVE-2025-63465 is on network availability. Organizations using Totolink LR350 routers may experience unexpected device crashes leading to loss of internet connectivity and disruption of internal network services. This can affect business continuity, especially for small businesses or remote offices relying on these routers for critical communications. Although the vulnerability does not directly expose sensitive data or allow unauthorized access, the resulting denial of service can hinder operational effectiveness and potentially delay critical processes. In sectors such as healthcare, finance, or public services where network uptime is crucial, even short outages can have significant consequences. Additionally, widespread exploitation could lead to larger-scale disruptions if attackers target multiple devices simultaneously. The lack of authentication requirement means attackers can exploit the vulnerability remotely without prior access, increasing the threat surface. European organizations with limited IT support or delayed patch management may be particularly vulnerable to exploitation.

Since no official patch or firmware update is currently available, organizations should implement immediate network-level mitigations. These include restricting access to the router’s management interfaces by IP filtering or firewall rules to allow only trusted sources. Monitoring network traffic for unusual or malformed requests targeting the ssid parameter can help detect exploitation attempts. Disabling remote management features on the router, if enabled, reduces exposure to external attackers. Organizations should also inventory their network devices to identify any Totolink LR350 routers and plan for prompt firmware updates once a patch is released. Employing network segmentation can limit the impact of a compromised or crashed router on critical systems. Regular backups of router configurations and quick recovery procedures will minimize downtime in case of an attack. Finally, educating users and administrators about this vulnerability and encouraging vigilance against suspicious network behavior will enhance overall security posture.