CVE-2025-55483 is a buffer overflow vulnerability identified in the Tenda AC6 router firmware version V15.03.06.23_multi. The vulnerability exists in the function formSetMacFilterCfg, which processes parameters macFilterType and deviceList. Buffer overflow vulnerabilities occur when input data exceeds the allocated buffer size, potentially allowing an attacker to overwrite adjacent memory. This can lead to arbitrary code execution, denial of service, or system crashes. In this case, the vulnerability is triggered by malformed input to the MAC filter configuration parameters, which are typically used to control network access based on device MAC addresses. Exploiting this flaw could allow an attacker to execute code with the privileges of the router’s firmware process, potentially gaining control over the device or disrupting network operations. The vulnerability does not currently have a CVSS score, and no known exploits have been reported in the wild as of the publication date. The lack of patch information suggests that a fix may not yet be available, increasing the urgency for affected users to implement mitigations. Given that Tenda AC6 routers are consumer-grade networking devices, this vulnerability could be exploited remotely if the router’s management interface is exposed or accessible via the local network, especially if authentication mechanisms are weak or absent. The vulnerability’s exploitation complexity depends on the accessibility of the vulnerable function and the ability to send crafted requests to the router’s configuration interface.

For European organizations, the impact of this vulnerability could be significant, particularly for small and medium enterprises (SMEs) and home office environments that rely on Tenda AC6 routers for network connectivity. Successful exploitation could lead to unauthorized control of the router, allowing attackers to intercept, modify, or disrupt network traffic, potentially leading to data breaches or network outages. This could compromise the confidentiality and integrity of sensitive communications and disrupt business operations. Additionally, compromised routers could be leveraged as entry points for lateral movement within corporate networks or as part of botnets for broader attacks. The impact is heightened in environments where these routers are deployed without adequate network segmentation or monitoring. Given the absence of known exploits, the immediate risk may be moderate, but the potential for future exploitation remains, especially if the vulnerability becomes publicly known without a timely patch.

Organizations using Tenda AC6 routers should immediately assess their exposure to this vulnerability. Specific mitigation steps include: 1) Restrict access to the router’s management interface by disabling remote administration or limiting it to trusted IP addresses. 2) Implement strong authentication mechanisms for router management, including complex passwords and, if supported, multi-factor authentication. 3) Monitor network traffic for unusual activity that could indicate exploitation attempts, such as unexpected configuration changes or anomalous packets targeting MAC filter settings. 4) Segment the network to isolate critical systems from devices connected via vulnerable routers, reducing potential lateral movement. 5) Regularly check for firmware updates from Tenda and apply patches promptly once available. 6) As an interim measure, consider replacing vulnerable devices with alternative hardware from vendors with robust security track records if patching is delayed. 7) Educate users about the risks of exposing router management interfaces and encourage best practices for network device security.