CVE-2022-45508 is a high-severity stack overflow vulnerability identified in the Tenda W30E router firmware version V1.0.1.25(633). The vulnerability arises from improper handling of the 'new_account' parameter in the HTTP endpoint /goform/editUserName. Specifically, the stack overflow occurs when the input to this parameter exceeds the expected buffer size, leading to memory corruption. This type of vulnerability is classified under CWE-787 (Out-of-bounds Write). Exploiting this flaw does not require any authentication or user interaction, and it can be triggered remotely over the network (AV:N), making it accessible to unauthenticated attackers. The CVSS v3.1 base score is 7.5, reflecting a high severity primarily due to the potential for denial of service (availability impact) rather than confidentiality or integrity impacts. The vulnerability does not appear to allow direct code execution or data manipulation but can cause the device to crash or reboot, disrupting network availability. No public exploits or patches have been reported as of the publication date (December 8, 2022). The affected product is the Tenda W30E router, a consumer-grade networking device commonly used for home and small office internet connectivity. The lack of vendor project and product details in the source information suggests limited public documentation, but the vulnerability is confirmed by MITRE and enriched by CISA data. Given the nature of the vulnerability, attackers could leverage it to cause network outages or degrade service quality by repeatedly triggering the overflow condition remotely, impacting the router's availability.

For European organizations, especially small businesses and home offices relying on Tenda W30E routers, this vulnerability poses a risk of network disruption through denial of service attacks. While it does not compromise confidentiality or integrity directly, the loss of availability can interrupt business operations, remote work, and critical communications. In sectors where continuous internet connectivity is essential—such as healthcare, finance, or critical infrastructure support—such disruptions could have cascading effects. Additionally, since the vulnerability can be exploited without authentication or user interaction, attackers could scan for vulnerable devices across European IP ranges and launch widespread denial of service campaigns. This could be particularly impactful in regions with high adoption of Tenda networking equipment or where alternative network infrastructure is limited. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, as attackers could develop exploits given the public disclosure. The impact is more pronounced for organizations lacking robust network segmentation or fallback connectivity options.

1. Immediate mitigation involves isolating or segmenting Tenda W30E devices from critical network segments to limit potential disruption. 2. Network administrators should monitor traffic to the /goform/editUserName endpoint for abnormal or oversized requests targeting the 'new_account' parameter, using intrusion detection systems (IDS) or web application firewalls (WAF) with custom rules. 3. Where possible, restrict remote management access to trusted IP addresses or disable remote HTTP management interfaces entirely. 4. Implement network-level rate limiting to reduce the risk of repeated exploitation attempts causing denial of service. 5. Regularly check for firmware updates from Tenda or security advisories that may provide patches or workarounds. 6. Consider replacing vulnerable devices with models from vendors with stronger security track records if patching is not feasible. 7. Educate users and IT staff about the risks of unpatched consumer-grade routers and encourage best practices for device management and network segmentation. 8. Employ network monitoring tools to detect unusual device reboots or connectivity losses that may indicate exploitation attempts.