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 resides in the formSetRemoteDhcpForAp function, which is accessible via the /goform/setDhcpAP HTTP endpoint. This function processes parameters related to DHCP configuration such as startip, endip, leasetime, gateway, dns1, and dns2. Improper validation or bounds checking of these input parameters allows an attacker to overflow a stack buffer, leading to memory corruption. Because the endpoint is remotely accessible and does not require authentication or user interaction, an attacker can exploit this flaw over the network without prior access. Successful exploitation could enable arbitrary code execution with elevated privileges on the router, potentially allowing attackers to take full control of the device. This can lead to network disruption, interception or manipulation of traffic, and pivoting to internal networks. The vulnerability has a CVSS 4.0 score of 8.7, reflecting its high impact and ease of exploitation. While no active exploitation in the wild has been reported, the availability of exploit code increases the likelihood of attacks. No official patches have been linked yet, so mitigation relies on network-level protections and configuration changes.

The impact of CVE-2025-15252 is significant for organizations using Tenda M3 routers. Exploitation can result in full compromise of the affected device, allowing attackers to execute arbitrary code with system-level privileges. This can lead to unauthorized access to internal networks, interception and manipulation of sensitive data, disruption of network services, and use of the device as a foothold for further attacks. The confidentiality, integrity, and availability of network communications are all at risk. Given the router’s role as a gateway device, compromise can affect entire organizational networks, including critical infrastructure and business operations. The remote, unauthenticated nature of the exploit increases the threat level, especially in environments where these routers are exposed to untrusted networks or the internet. The lack of a patch at the time of disclosure further elevates risk, necessitating immediate mitigation measures.

1. Immediately isolate affected Tenda M3 routers from untrusted networks, especially the internet, to prevent remote exploitation. 2. Implement strict firewall rules to block access to the /goform/setDhcpAP endpoint or restrict management interfaces to trusted IP addresses only. 3. Monitor network traffic for unusual requests targeting DHCP configuration endpoints and signs of exploitation attempts. 4. Disable remote management features on the router if not required to reduce the attack surface. 5. Regularly check for firmware updates from Tenda and apply patches as soon as they become available. 6. Consider replacing affected devices with alternative hardware if patches are delayed or unavailable. 7. Employ network segmentation to limit the impact of a compromised router on critical systems. 8. Conduct security awareness training for network administrators to recognize and respond to exploitation indicators. 9. Use intrusion detection/prevention systems (IDS/IPS) tuned to detect buffer overflow attempts targeting router management interfaces. 10. Maintain up-to-date backups of router configurations to enable rapid recovery if compromise occurs.