CVE-2025-57064 is a high-severity vulnerability identified in the Tenda G3 router firmware version 3.0br_V15.11.0.17. The vulnerability arises from a stack-based buffer overflow in the handling of the 'bindDhcpIndex' parameter within the 'modifyDhcpRule' function. This function is likely part of the router's DHCP configuration management interface. An attacker can exploit this flaw by sending a specially crafted request containing malicious input for the 'bindDhcpIndex' parameter. Due to improper bounds checking, the crafted input causes a stack overflow, which can lead to a Denial of Service (DoS) condition by crashing the device or causing it to become unresponsive. The vulnerability does not require any authentication or user interaction, and can be exploited remotely over the network, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The impact is limited to availability disruption, with no direct confidentiality or integrity compromise reported. The vulnerability is classified under CWE-121 (Stack-based Buffer Overflow), a common and well-understood software weakness. No known exploits are currently reported in the wild, and no patches have been linked yet. Given the nature of the vulnerability, attackers can cause service outages on affected devices, potentially disrupting network connectivity for users relying on these routers.

For European organizations, the impact of this vulnerability can be significant, especially for small and medium enterprises or home office environments that use Tenda G3 routers for internet connectivity. A successful exploitation would result in denial of service, causing network outages and loss of internet access. This can disrupt business operations, communications, and access to cloud services. While the vulnerability does not directly compromise data confidentiality or integrity, the availability impact can affect productivity and operational continuity. In sectors where continuous connectivity is critical, such as healthcare, finance, or critical infrastructure, even short outages can have cascading effects. Additionally, if attackers use this vulnerability as part of a larger attack chain, it could serve as a foothold or distraction while other attacks are conducted. The lack of authentication requirement increases the risk, as attackers can exploit the vulnerability remotely without prior access. Organizations relying on Tenda G3 routers should consider the risk of targeted or opportunistic attacks exploiting this flaw.

To mitigate this vulnerability, organizations should first verify if their network infrastructure includes Tenda G3 routers running firmware version 3.0br_V15.11.0.17. Immediate steps include isolating affected devices from untrusted networks or restricting access to the router's management interfaces using firewall rules or network segmentation. Since no official patch is currently available, monitoring vendor communications for firmware updates is critical. As a temporary workaround, disabling remote management features or restricting management access to trusted IP addresses can reduce exposure. Network administrators should also implement intrusion detection or prevention systems (IDS/IPS) with signatures to detect anomalous DHCP configuration requests targeting the 'bindDhcpIndex' parameter. Regularly auditing router configurations and logs for unusual activity can help identify exploitation attempts early. Finally, organizations should plan for timely firmware updates once patches are released and consider replacing affected devices if no fix is forthcoming.