CVE-2022-45512 is a high-severity vulnerability identified in the Tenda W30E router firmware version V1.0.1.25(633). The vulnerability is a stack-based buffer overflow triggered via the 'page' parameter in the /goform/SafeEmailFilter endpoint. A stack overflow occurs when more data is written to a buffer located on the stack than it can hold, potentially overwriting adjacent memory and leading to arbitrary code execution or denial of service. In this case, the vulnerability can be exploited remotely over the network without any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The vulnerability impacts availability (A:H) but does not affect confidentiality or integrity directly. Although no known exploits are currently reported in the wild, the ease of exploitation and lack of required privileges make this a significant risk. The absence of vendor or product details beyond the Tenda W30E model limits the scope of affected devices to this specific router model and firmware version. The CWE classification CWE-787 confirms this is a classic stack-based buffer overflow issue. Given the nature of the vulnerability, an attacker could potentially cause the device to crash or execute arbitrary code, leading to network disruption or further compromise of the router and connected devices. The lack of available patches or mitigation from the vendor at this time increases the urgency for affected users to take protective measures.

For European organizations, especially small and medium enterprises or residential users relying on Tenda W30E routers, this vulnerability poses a risk of network outages or compromise of network infrastructure. The router is typically used in home or small office environments, so critical infrastructure impact may be limited. However, disruption of internet connectivity or potential pivoting from compromised routers to internal networks could lead to operational downtime and data exposure. The vulnerability's remote exploitability without authentication increases the attack surface, potentially allowing attackers to launch denial-of-service attacks or gain control over the device to intercept or manipulate network traffic. This could be particularly impactful for organizations with limited IT security resources or those using these routers in less monitored network segments. Additionally, the lack of patches means organizations must rely on network-level mitigations or device replacement to reduce risk. The impact on confidentiality and integrity is currently rated as none, but successful exploitation could be leveraged in multi-stage attacks.

1. Immediate mitigation should include isolating the affected Tenda W30E routers from critical network segments and restricting inbound access to the router's management interfaces, especially blocking access to the /goform/SafeEmailFilter endpoint from untrusted networks. 2. Employ network-level protections such as intrusion detection/prevention systems (IDS/IPS) configured to detect anomalous HTTP requests targeting the vulnerable parameter. 3. Where possible, replace the affected Tenda W30E devices with routers from vendors with active security support and patch management. 4. Monitor network traffic for unusual activity or signs of exploitation attempts targeting this vulnerability. 5. If replacement is not immediately feasible, consider deploying firewall rules to limit access to the router's web interface to trusted IP addresses only. 6. Maintain up-to-date asset inventories to identify all devices running the vulnerable firmware version. 7. Engage with Tenda support channels to request firmware updates or patches and subscribe to vulnerability advisories for timely updates. 8. Educate users about the risks of using outdated or unsupported network devices and encourage regular firmware updates where available.