CVE-2025-57085 is a stack overflow vulnerability identified in the Tenda W30E router firmware version V16.01.0.19 (build 5037). The flaw resides in the handling of the 'v17' parameter within the UploadCfg function. This function is presumably responsible for processing configuration uploads to the device. An attacker can exploit this vulnerability by sending a specially crafted request containing a maliciously crafted 'v17' parameter that triggers a stack overflow condition. This overflow can lead to memory corruption, which in this case results in a Denial of Service (DoS) condition, causing the device to crash or become unresponsive. The vulnerability does not appear to require authentication or user interaction, increasing its risk profile. There are no known exploits in the wild at the time of publication, and no patches or mitigations have been officially released. The lack of a CVSS score means the severity must be assessed based on the impact and exploitability characteristics. Since the vulnerability causes a DoS rather than remote code execution, the impact is primarily on availability. However, given the critical role of routers in network infrastructure, such a DoS can disrupt connectivity for all devices relying on the affected router. The vulnerability affects a specific Tenda router model and firmware version, which limits the scope but still poses a significant risk to environments using this hardware.

For European organizations, the impact of this vulnerability can be significant, particularly for small and medium enterprises or home office setups that rely on Tenda W30E routers for their network connectivity. A successful DoS attack could disrupt business operations by cutting off internet access or internal network communication, leading to productivity losses and potential operational downtime. Critical sectors such as healthcare, finance, and public services that depend on continuous network availability could face service interruptions. Additionally, the disruption could be exploited as part of a larger attack chain, for example, to distract IT teams while other attacks are conducted. Since the vulnerability does not require authentication, attackers can potentially launch attacks remotely if the device’s management interface is exposed to untrusted networks, increasing the risk for organizations with less secure network configurations. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once the vulnerability details become widely known.

Organizations should immediately identify any Tenda W30E devices running firmware version V16.01.0.19 (5037) within their networks. Since no official patch is currently available, mitigation should focus on reducing exposure. This includes disabling remote management interfaces accessible from untrusted networks, restricting access to the device management interface to trusted IP addresses only, and implementing network segmentation to isolate vulnerable devices. Monitoring network traffic for unusual or malformed requests targeting the UploadCfg function or the 'v17' parameter could help detect exploitation attempts. Organizations should also consider replacing vulnerable devices with models from vendors that provide timely security updates. Regularly checking for firmware updates from Tenda and applying them promptly once available is critical. Additionally, implementing intrusion detection/prevention systems (IDS/IPS) that can detect anomalous traffic patterns may help mitigate exploitation attempts. Finally, maintaining robust backup and recovery procedures will minimize operational impact in case of a successful DoS attack.