CVE-2024-0927 is a stack-based buffer overflow vulnerability identified in the Tenda AC10U router, specifically affecting firmware version 15.03.06.49_multi_TDE01. The vulnerability resides in the function fromAddressNat, where improper handling and manipulation of the arguments entrys, mitInterface, or page can lead to a stack-based buffer overflow condition. This type of vulnerability occurs when data exceeding the buffer's boundary is written to the stack, potentially overwriting adjacent memory, including control flow data such as return addresses. Exploiting this vulnerability remotely is possible, meaning an attacker does not require physical access to the device but can launch attacks over the network. The vulnerability has been publicly disclosed, and although no known exploits are currently observed in the wild, the disclosure increases the risk of exploitation attempts. The vendor, Tenda, was contacted early regarding this issue but has not provided any response or patch, leaving affected devices unprotected. The CVSS v3.1 base score is 4.7, indicating a medium severity level. The vector string (AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L) shows that the attack can be performed remotely (Network), requires low attack complexity, but needs high privileges (PR:H) on the device, no user interaction is needed, and the impact affects confidentiality, integrity, and availability to a low extent. The vulnerability is classified under CWE-121, which corresponds to stack-based buffer overflows, a well-known and critical class of memory corruption vulnerabilities that can lead to arbitrary code execution or denial of service if successfully exploited.

For European organizations, the impact of CVE-2024-0927 can be significant, especially for those relying on Tenda AC10U routers in their network infrastructure. Although the CVSS score is medium, the potential for remote exploitation of a stack-based buffer overflow can lead to unauthorized code execution, service disruption, or compromise of network traffic confidentiality and integrity. This could result in network outages, interception or manipulation of sensitive data, and potential lateral movement within corporate networks. The lack of vendor response and absence of patches exacerbate the risk, as organizations must rely on mitigations or device replacement. Given that routers are critical network edge devices, their compromise can undermine the security posture of entire organizational networks. This is particularly concerning for sectors with high security requirements such as finance, healthcare, and government institutions in Europe. Additionally, the exposure of home or small office routers can serve as entry points for attackers targeting remote workers or branch offices, which are common in European distributed enterprise environments.

Since no official patch or vendor response is available, European organizations should implement specific mitigations to reduce exposure: 1) Identify and inventory all Tenda AC10U devices running the affected firmware version (15.03.06.49_multi_TDE01) within the network. 2) Immediately isolate these devices from untrusted networks or restrict management interfaces to trusted internal networks only, using firewall rules or VLAN segmentation. 3) Disable remote management features if enabled, especially those accessible from the internet. 4) Monitor network traffic for unusual activity targeting the fromAddressNat function or related NAT configuration interfaces, using IDS/IPS signatures or anomaly detection tools. 5) Consider replacing affected Tenda AC10U routers with alternative devices from vendors with active security support and patching policies. 6) Implement strict access controls requiring multi-factor authentication for administrative access to routers to mitigate the high privilege requirement for exploitation. 7) Regularly review and update network device firmware and configurations to maintain security hygiene. 8) Stay informed on any future vendor updates or community-developed patches addressing this vulnerability.