CVE-2025-15230 identifies a heap-based buffer overflow vulnerability in the Tenda M3 router firmware version 1.0.0.13(4903). The flaw exists in the formSetVlanPolicy function, specifically in the handling of the qvlan_truck_port parameter within the /goform/setVlanPolicyData endpoint. This parameter is improperly validated, allowing an attacker to manipulate it to overflow a heap buffer. The vulnerability can be exploited remotely over the network without requiring authentication or user interaction, making it highly accessible to attackers. Successful exploitation could lead to arbitrary code execution on the device or cause a denial of service by crashing the router. The vulnerability affects the confidentiality, integrity, and availability of the device and potentially the network it supports. Although no active exploits have been observed in the wild, the exploit code has been publicly released, increasing the risk of imminent attacks. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). The vulnerability is critical for organizations relying on Tenda M3 routers, especially in environments where these devices are exposed to untrusted networks. No official patches have been linked yet, so mitigation relies on network controls and monitoring until a firmware update is available.

For European organizations, this vulnerability poses a significant risk to network infrastructure security. Tenda M3 routers are commonly used in small and medium-sized businesses and home office environments, which may lack robust security controls. Exploitation could allow attackers to gain control over the router, intercept or manipulate network traffic, and disrupt internet connectivity. This could lead to data breaches, lateral movement within corporate networks, and operational downtime. The high severity and ease of exploitation increase the likelihood of targeted attacks or opportunistic scanning by cybercriminals. Critical sectors such as finance, healthcare, and government agencies using vulnerable devices could face severe confidentiality and availability impacts. Additionally, compromised routers could be leveraged as entry points for broader attacks or as part of botnets for distributed denial-of-service (DDoS) campaigns. The lack of authentication and user interaction requirements further exacerbates the threat, making remote exploitation feasible even by relatively unsophisticated attackers.

1. Immediate mitigation should focus on network-level protections such as implementing strict firewall rules to block inbound access to the /goform/setVlanPolicyData endpoint from untrusted networks. 2. Deploy intrusion detection and prevention systems (IDS/IPS) with signatures or heuristics to detect anomalous requests targeting the qvlan_truck_port parameter. 3. Segment networks to isolate vulnerable Tenda M3 routers from critical infrastructure and sensitive data environments. 4. Monitor router logs for unusual activity or repeated attempts to access the vulnerable endpoint. 5. Engage with Tenda support channels to obtain firmware updates or security advisories addressing this vulnerability. 6. If no patch is available, consider replacing affected devices with alternative hardware from vendors with timely security support. 7. Educate network administrators about the risks and signs of exploitation attempts. 8. Regularly audit network devices for outdated firmware and apply updates promptly once available. 9. Employ network access controls to restrict management interfaces to trusted IP addresses only. 10. Conduct penetration testing and vulnerability assessments to verify the effectiveness of implemented controls.