CVE-2025-30256 identifies a denial of service vulnerability in the Tenda AC6 V5.0 router firmware version V02.03.01.110. The root cause is a missing release of resources after their effective lifetime during HTTP header parsing, classified under CWE-772. This resource leak leads to exhaustion of critical system resources when the device processes a specially crafted series of HTTP requests. An attacker can remotely send multiple network packets without requiring authentication or user interaction to trigger repeated device reboots, effectively causing a denial of service. The vulnerability affects the router's availability but does not compromise confidentiality or integrity. The CVSS 3.1 score of 8.6 (AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H) indicates a network attack vector with low complexity and no privileges or user interaction needed, with a scope change due to the device reboot affecting connected systems. No patches have been published yet, and no exploits are known in the wild, but the vulnerability is publicly disclosed and documented by Talos and the CVE database. The impact is primarily on network availability, potentially disrupting business operations relying on these routers for connectivity.

For European organizations, the primary impact is disruption of network availability due to forced reboots of Tenda AC6 routers. This can lead to intermittent or prolonged loss of internet connectivity, affecting business continuity, remote work, and access to cloud services. Critical infrastructure sectors such as finance, healthcare, and manufacturing that rely on stable network environments may experience operational delays or outages. The vulnerability could also be leveraged as part of a larger attack chain to cause widespread denial of service in enterprise or ISP networks deploying these devices. Although confidentiality and integrity are not directly impacted, the loss of availability can have cascading effects on security monitoring, incident response, and service delivery. The lack of authentication or user interaction requirements increases the risk of automated exploitation attempts, especially in exposed network segments.

Organizations should monitor Tenda's official channels for firmware updates addressing CVE-2025-30256 and apply patches immediately upon release. In the interim, network administrators should implement access control lists (ACLs) or firewall rules to restrict HTTP access to the management interface of Tenda AC6 routers from untrusted networks. Deploying network intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection for abnormal HTTP header patterns may help detect or block exploit attempts. Segmentation of network zones to isolate critical devices and limiting exposure of router management interfaces to the internet can reduce attack surface. Regularly auditing device firmware versions and maintaining an inventory of affected hardware will aid in prioritizing remediation. Additionally, organizations should prepare incident response plans for potential denial of service events impacting network infrastructure.