CVE-2025-11388 is a stack-based buffer overflow vulnerability identified in the Tenda AC15 router firmware version 15.03.05.18. The flaw exists in the handling of the 'newVersion' parameter within the /goform/setNotUpgrade endpoint, which is part of the router's web management interface. When an attacker sends a specially crafted request manipulating this parameter, it causes a buffer overflow on the stack, potentially overwriting the return address or other control data. This vulnerability can be exploited remotely without authentication or user interaction, as the affected endpoint is accessible over the network. The buffer overflow enables attackers to execute arbitrary code with the privileges of the router's web server process, which typically runs with elevated permissions. This could allow attackers to take full control of the device, modify configurations, intercept or redirect network traffic, or use the device as a foothold for further attacks within the network. The CVSS 4.0 base score of 8.7 reflects the high impact on confidentiality, integrity, and availability, combined with the ease of exploitation (network attack vector, no privileges or user interaction required). Although no active exploitation in the wild has been reported, the availability of a public exploit increases the likelihood of future attacks. The vulnerability underscores the importance of secure input validation and memory management in embedded device firmware, especially for network-facing services.

The impact of CVE-2025-11388 is significant for organizations using Tenda AC15 routers, particularly those running the vulnerable firmware version 15.03.05.18. Successful exploitation can lead to complete compromise of the router, allowing attackers to execute arbitrary code remotely. This can result in unauthorized access to internal networks, interception or manipulation of sensitive data, disruption of network services, and potential lateral movement to other critical systems. Given that routers serve as the gateway for network traffic, a compromised device can undermine the security posture of the entire organization. Small and medium enterprises, home users, and even larger organizations relying on these devices for internet connectivity or network segmentation are at risk. The availability of a public exploit increases the urgency for mitigation. Additionally, compromised routers can be enlisted into botnets or used for launching further attacks, amplifying the threat landscape globally.

To mitigate CVE-2025-11388, organizations should immediately check if they are running Tenda AC15 devices with firmware version 15.03.05.18. Since no official patch links are currently provided, users should monitor Tenda's official channels for firmware updates addressing this vulnerability and apply them promptly once available. In the interim, network administrators should restrict access to the router's management interface by limiting it to trusted internal networks and disabling remote management if enabled. Implement network segmentation to isolate critical systems from vulnerable devices. Employ intrusion detection or prevention systems to monitor for exploit attempts targeting the /goform/setNotUpgrade endpoint. Additionally, consider replacing affected devices with models from vendors with a stronger security track record if timely patches are not forthcoming. Regularly audit and update router firmware as part of a comprehensive device management policy to reduce exposure to similar vulnerabilities.