CVE-2025-15252 is a stack-based buffer overflow vulnerability identified in the Tenda M3 router firmware version 1.0.0.13(4903). The vulnerability exists in the formSetRemoteDhcpForAp function, which processes parameters such as startip, endip, leasetime, gateway, dns1, and dns2 via the /goform/setDhcpAP endpoint. Improper validation or sanitization of these parameters allows an attacker to overflow a stack buffer, potentially overwriting the return address or other control data on the stack. This can lead to arbitrary code execution with elevated privileges on the device. The attack vector is remote and does not require authentication or user interaction, increasing the risk of exploitation. The CVSS 4.0 score is 8.7 (high), reflecting the ease of exploitation (network attack vector, low attack complexity), no privileges required, and high impact on confidentiality, integrity, and availability. While no active exploits have been observed in the wild, a proof-of-concept exploit has been published, indicating that exploitation is feasible. The vulnerability affects a specific firmware version, and no official patches or mitigations have been linked yet. The flaw could be leveraged to compromise network infrastructure, intercept or manipulate traffic, or pivot into internal networks.

For European organizations, exploitation of this vulnerability could lead to full compromise of affected Tenda M3 routers, which are often used in small office/home office (SOHO) and some enterprise environments. Successful attacks could result in unauthorized access to internal networks, interception of sensitive data, disruption of network services, and deployment of persistent malware or botnets. This is particularly concerning for critical infrastructure sectors, government agencies, and businesses relying on these devices for secure connectivity. The vulnerability undermines the confidentiality, integrity, and availability of network communications. Given the remote and unauthenticated nature of the exploit, attackers can target vulnerable devices at scale, increasing the risk of widespread disruption. The lack of current patches means organizations must rely on network-level mitigations and monitoring until vendor updates are available.

1. Immediately restrict access to the router’s management interface by limiting exposure to trusted networks only, preferably via VPN or internal network segments. 2. Implement network segmentation to isolate vulnerable devices from critical infrastructure and sensitive data stores. 3. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics to detect attempts to exploit the /goform/setDhcpAP endpoint. 4. Monitor network traffic for unusual or malformed requests targeting DHCP configuration endpoints. 5. Disable remote management features on Tenda M3 devices if not strictly necessary. 6. Regularly check for firmware updates from Tenda and apply patches as soon as they become available. 7. Consider replacing affected devices with models from vendors with stronger security track records if patching is delayed. 8. Educate IT staff about this vulnerability and ensure incident response plans include steps for router compromise scenarios.