CVE-2024-0926 is a stack-based buffer overflow vulnerability identified in the Tenda AC10U router, specifically affecting firmware version 15.03.06.49_multi_TDE01. The flaw resides in the function formWifiWpsOOB, where improper handling of the 'index' argument allows an attacker to overwrite the stack memory. This vulnerability can be triggered remotely without user interaction, making it a significant risk. Although the CVSS score is rated medium (4.7), the vulnerability impacts confidentiality, integrity, and availability due to the potential for arbitrary code execution or denial of service. The vulnerability is classified under CWE-121, which relates to stack-based buffer overflows, a common and dangerous class of software errors. The vendor, Tenda, was contacted but did not respond or provide a patch at the time of disclosure. No known exploits are currently reported in the wild, but public disclosure increases the risk of exploitation attempts. The vulnerability requires high privileges (PR:H) to exploit, which may limit the attack surface somewhat, but the remote attack vector (AV:N) and lack of required user interaction (UI:N) still make it a concern for exposed devices. The scope is unchanged (S:U), meaning the impact is limited to the vulnerable component itself.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on Tenda AC10U routers in their network infrastructure. Successful exploitation could allow attackers to execute arbitrary code, potentially leading to network compromise, interception of sensitive data, or disruption of network services. This could affect confidentiality by exposing internal communications, integrity by allowing manipulation of network traffic or device configurations, and availability by causing device crashes or denial of service. Given the remote exploitability and absence of user interaction, attackers could target these routers en masse, potentially affecting home offices, small businesses, or branch offices using this device. The lack of vendor response and patch availability increases the risk for European entities, as they may need to rely on network-level mitigations or device replacement. Additionally, the medium CVSS score may underestimate the real-world impact if combined with other vulnerabilities or misconfigurations.

Since no official patch is available, European organizations should implement specific mitigations: 1) Isolate Tenda AC10U devices from direct internet exposure by placing them behind firewalls or using network segmentation to limit remote access to the vulnerable function. 2) Disable WPS functionality if possible, as the vulnerability is in the WPS-related function formWifiWpsOOB, reducing the attack surface. 3) Monitor network traffic for unusual activity targeting the router, especially malformed packets attempting to exploit the index parameter. 4) Employ intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics for buffer overflow attempts against Tenda routers. 5) Consider replacing affected devices with alternative models from vendors with active security support if patching is not forthcoming. 6) Maintain up-to-date inventories of network devices to quickly identify and remediate vulnerable units. 7) Restrict administrative access to the device to trusted internal networks and use strong authentication mechanisms to prevent privilege escalation required for exploitation.