CVE-2025-44900 is a medium severity vulnerability identified in the Tenda RX3 router firmware version V1.0br_V16.03.13.11. The vulnerability exists in the GetParentControlInfo function accessible via the web URL /goform/GetParentControlInfo. Specifically, the issue arises from improper handling of the 'mac' parameter, which can be manipulated to trigger a stack-based buffer overflow (CWE-121). This type of vulnerability occurs when data exceeding the buffer's capacity is written to the stack, potentially overwriting adjacent memory and leading to unpredictable behavior such as crashes or arbitrary code execution. According to the CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N), the vulnerability is remotely exploitable over the network without requiring authentication or user interaction, with low attack complexity. The impact affects confidentiality and integrity but does not directly affect availability. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability was reserved on 2025-04-22 and published on 2025-05-06. The lack of vendor or product details beyond the Tenda RX3 firmware version limits the scope of affected devices, but given the nature of consumer routers, this vulnerability could be leveraged by attackers to gain unauthorized access or manipulate router configurations if exploited successfully.

For European organizations, the exploitation of this vulnerability could lead to unauthorized disclosure of sensitive network information and potential manipulation of router settings, undermining network security and privacy. Since routers like the Tenda RX3 are often used in small offices and home environments, compromised devices could serve as entry points for lateral movement into corporate networks, especially in remote work scenarios. The confidentiality and integrity impacts could result in interception or alteration of network traffic, potentially exposing corporate credentials or sensitive communications. Although availability impact is not indicated, the exploitation could facilitate further attacks such as man-in-the-middle or persistent backdoors. The absence of authentication requirements and user interaction increases the risk, particularly for organizations with less stringent network perimeter defenses or those using these routers in critical network segments.

Organizations should immediately inventory their network devices to identify any Tenda RX3 routers running the vulnerable firmware version V1.0br_V16.03.13.11. Until an official patch is released, network administrators should restrict access to the router management interface by implementing network segmentation and firewall rules that limit access to trusted IP addresses only. Disabling remote management features and changing default credentials can reduce exposure. Monitoring network traffic for unusual requests to the /goform/GetParentControlInfo endpoint and anomalous MAC parameter values can help detect exploitation attempts. Employing intrusion detection/prevention systems with custom signatures targeting this URL and parameter manipulation is advisable. Additionally, organizations should engage with Tenda support channels to obtain firmware updates or mitigation guidance and plan for timely patch deployment once available. For critical environments, consider replacing vulnerable devices with models from vendors with robust security update policies.