CVE-2025-51082 is a stack-based buffer overflow vulnerability identified in the Tenda AC8V4 router firmware version V16.03.34.06. The vulnerability arises from improper handling of the 'timeZone' parameter in the /goform/fast_setting_wifi_set endpoint. Specifically, when an attacker manipulates the 'timeZone' argument, it leads to a stack overflow condition. This type of vulnerability typically allows an attacker to overwrite parts of the stack memory, potentially enabling arbitrary code execution, denial of service, or system crashes. Since the vulnerability is located in a web form handler, it is likely exploitable remotely via crafted HTTP requests to the router's management interface. The absence of a CVSS score and known exploits in the wild suggests this is a newly disclosed vulnerability with limited public exploitation information. However, stack overflows in router firmware are critical because they can compromise the device's integrity and availability, potentially allowing attackers to gain control over network traffic or use the device as a foothold for further attacks.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on Tenda AC8V4 routers in their network infrastructure. Compromise of these routers could lead to unauthorized access to internal networks, interception or manipulation of sensitive data, and disruption of network services. Given that routers serve as gateways to organizational networks, exploitation could facilitate lateral movement by attackers, data exfiltration, or launching attacks against other internal systems. Additionally, compromised routers can be enlisted into botnets, amplifying the scale of attacks such as distributed denial of service (DDoS). The impact is heightened for sectors with stringent data protection requirements under GDPR, as breaches involving network devices can lead to regulatory penalties and reputational damage.

To mitigate this vulnerability, organizations should first verify if their Tenda AC8V4 routers are running the vulnerable firmware version V16.03.34.06. If so, they should immediately seek firmware updates or patches from Tenda, even though no patch links are currently available; contacting vendor support is recommended. In the interim, restrict access to the router's management interface by limiting it to trusted internal IP addresses and disabling remote management if enabled. Implement network segmentation to isolate critical systems from affected routers. Employ intrusion detection systems (IDS) to monitor for anomalous HTTP requests targeting /goform/fast_setting_wifi_set or unusual traffic patterns. Regularly audit router configurations and logs for signs of exploitation. Finally, consider replacing vulnerable hardware if patches are not forthcoming in a timely manner.