CVE-2025-8017 is a critical stack-based buffer overflow vulnerability identified in the Tenda AC7 router, specifically affecting firmware version 15.03.06.44. The flaw resides in the HTTP daemon component (httpd), within the function formSetMacFilterCfg, which processes the /goform/setMacFilterCfg endpoint. The vulnerability arises from improper handling of the deviceList argument, allowing an attacker to manipulate input data to overflow a stack buffer. This overflow can lead to arbitrary code execution or cause the device to crash, resulting in denial of service. The vulnerability is remotely exploitable without authentication or user interaction, increasing the risk of widespread exploitation. Although no public exploits are currently observed in the wild, the exploit code has been disclosed publicly, raising the likelihood of imminent attacks. The CVSS v4.0 base score of 8.7 reflects high severity, with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability affects a widely deployed consumer and small office/home office (SOHO) router model, which is often used as a gateway device, making it a critical point of compromise in network infrastructure.

For European organizations, this vulnerability poses significant risks. Compromise of Tenda AC7 routers can lead to unauthorized network access, interception or manipulation of sensitive data, and disruption of internet connectivity. Given that routers serve as the first line of defense and traffic control, attackers exploiting this flaw could pivot into internal networks, bypassing perimeter defenses. This is particularly concerning for small and medium enterprises (SMEs) and home office setups prevalent across Europe, which may rely on such consumer-grade devices without advanced security monitoring. The potential for remote code execution means attackers could install persistent malware, conduct espionage, or launch further attacks such as ransomware or data exfiltration. The lack of authentication requirement and ease of exploitation amplify the threat, potentially impacting confidentiality, integrity, and availability of organizational data and services.

Immediate mitigation steps include: 1) Upgrading the Tenda AC7 firmware to a patched version once released by the vendor; monitoring Tenda's official channels for updates is critical. 2) Until a patch is available, restrict remote management access to the router by disabling WAN-side HTTP/HTTPS access or limiting it via firewall rules to trusted IP addresses only. 3) Employ network segmentation to isolate vulnerable devices from critical infrastructure and sensitive data. 4) Monitor network traffic for unusual activity targeting the /goform/setMacFilterCfg endpoint or anomalous HTTP requests to the router. 5) Consider replacing affected devices with models from vendors with robust security update policies if patching is delayed. 6) Educate users and administrators about the risks of exposing router management interfaces to the internet. 7) Deploy intrusion detection/prevention systems (IDS/IPS) with signatures for this vulnerability once available.