The vulnerability identified as CVE-2025-63469 affects the Totolink LR350 router running firmware version 9.3.5u.6369_B20220309. It is a stack overflow vulnerability triggered via the ssid parameter processed in the sub_421BAC function. Stack overflow vulnerabilities occur when a program writes more data to a buffer located on the stack than it can hold, which can corrupt adjacent memory and lead to unpredictable behavior. In this case, the overflow can be induced by sending a specially crafted network request containing a malicious ssid parameter. The consequence of this overflow is a denial of service (DoS), where the router may crash or reboot, disrupting network availability. There is no indication that this vulnerability allows for remote code execution or privilege escalation, limiting the impact to availability. The vulnerability does not require authentication, meaning an attacker can exploit it remotely without credentials, increasing the risk. No patches or firmware updates are currently linked, and no known exploits have been observed in the wild, suggesting it is a newly disclosed issue. The affected version is specifically 9.3.5u.6369_B20220309, but no other versions are listed, so the scope may be limited to this firmware release. The vulnerability was reserved on 2025-10-27 and published on 2025-10-31, indicating recent discovery and disclosure.

For European organizations, the primary impact of CVE-2025-63469 is the potential disruption of network services due to router crashes or reboots caused by the stack overflow. This can lead to temporary loss of internet connectivity, affecting business operations, communications, and access to cloud services. Organizations relying on Totolink LR350 routers, especially in small office or home office environments, may face increased risk if these devices are exposed to untrusted networks or the internet. The lack of authentication requirement for exploitation means attackers can remotely trigger the DoS without prior access, increasing the threat surface. While the vulnerability does not compromise confidentiality or integrity directly, the availability impact can cause operational downtime and potential productivity losses. Additionally, repeated exploitation attempts could lead to network instability and increased support costs. The absence of known exploits in the wild currently limits immediate risk, but the vulnerability's public disclosure may prompt attackers to develop exploits. European sectors with critical reliance on stable network infrastructure, such as finance, healthcare, and government, could be indirectly affected if such devices are part of their network edge or remote access infrastructure.

To mitigate CVE-2025-63469, organizations should first identify any Totolink LR350 routers running the vulnerable firmware version 9.3.5u.6369_B20220309 within their network. Since no official patches are currently available, network administrators should implement compensating controls such as restricting access to router management interfaces via firewall rules or network segmentation to limit exposure to untrusted networks. Disabling remote management features or changing default management ports can reduce attack surface. Monitoring network traffic for unusual or malformed ssid parameter requests may help detect exploitation attempts. Organizations should maintain regular backups of router configurations to enable rapid recovery after a DoS event. Engaging with Totolink support or vendor channels to obtain firmware updates or security advisories is critical. Once a patch is released, prompt firmware upgrade is essential. Additionally, consider deploying network intrusion detection systems (NIDS) with signatures targeting malformed ssid requests to alert on potential attacks. For environments where Totolink devices are critical, evaluating alternative hardware with better security track records may be warranted.