CVE-2025-11527 identifies a critical stack-based buffer overflow vulnerability in the Tenda AC7 router firmware version 15.03.06.44. The vulnerability resides in an unspecified function related to the /goform/fast_setting_pppoe_set endpoint, which processes the Password parameter. By crafting a specially manipulated Password argument, an attacker can overflow the stack buffer, potentially overwriting return addresses or control data. This can lead to arbitrary code execution with elevated privileges on the device. The attack vector is remote network access, requiring no authentication or user interaction, making exploitation straightforward for attackers with network access to the device. The CVSS 4.0 score of 8.7 reflects the high impact on confidentiality, integrity, and availability, combined with low attack complexity and no required privileges. While no known exploits are currently active in the wild, the public disclosure of the vulnerability details increases the likelihood of exploitation attempts. The affected product, Tenda AC7, is a widely used consumer and small business router, often deployed in home and enterprise edge networks. Successful exploitation could allow attackers to gain control over the router, intercept or manipulate traffic, disrupt network availability, or pivot to internal networks. The lack of available patches at the time of disclosure necessitates immediate mitigation efforts to reduce exposure.

The impact of CVE-2025-11527 is significant for organizations and individuals using Tenda AC7 routers. Exploitation can lead to full compromise of the device, enabling attackers to execute arbitrary code with elevated privileges. This could result in interception or manipulation of network traffic, loss of confidentiality of sensitive data, disruption of network services, and potential lateral movement into internal networks. For enterprises, this could mean exposure of critical internal resources and data breaches. For home users, it could lead to unauthorized access to personal information and use of the device as part of botnets or other malicious activities. The remote, unauthenticated nature of the exploit increases the risk of widespread attacks, especially in environments where these routers are directly exposed to the internet. The absence of patches at disclosure time further exacerbates the risk, requiring organizations to implement compensating controls to protect their networks.

Given the absence of an official patch at the time of disclosure, organizations should implement the following specific mitigations: 1) Immediately restrict remote access to the router’s management interfaces, especially the /goform/fast_setting_pppoe_set endpoint, by disabling remote administration or limiting access to trusted IP addresses via firewall rules. 2) Segment the network to isolate the router management interface from untrusted networks and reduce exposure. 3) Monitor network traffic for unusual requests targeting the /goform/fast_setting_pppoe_set endpoint or anomalous patterns indicative of exploitation attempts. 4) If possible, downgrade or upgrade to a firmware version not affected by this vulnerability once available from the vendor. 5) Employ network intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics to detect exploitation attempts. 6) Educate users and administrators about the risk and ensure strong, unique passwords are used for router access to prevent secondary compromise. 7) Regularly check for vendor updates and apply patches promptly when released. These targeted actions go beyond generic advice by focusing on access control, monitoring, and network segmentation specific to the vulnerability’s attack vector.