CVE-2025-70747 identifies a stack overflow vulnerability in the Tenda AX-1806 router firmware version 1.0.0.1. The flaw exists in the handling of the serviceName parameter within the sub_65A28 function, where improper input validation allows an attacker to overflow the stack memory. This overflow can be triggered by sending a specially crafted request to the device, causing it to crash or reboot, resulting in a Denial of Service (DoS). The vulnerability does not require authentication, meaning an attacker with network access to the device can exploit it remotely. The absence of a CVSS score and patches indicates this is a newly disclosed issue with limited public information and no known active exploitation. The impact is primarily on device availability, potentially disrupting network operations dependent on the affected routers. The Tenda AX-1806 is a consumer-grade router, but it may also be deployed in small to medium enterprise environments or branch offices. The lack of authentication requirement and the straightforward nature of the exploit increase the risk profile. No mitigation patches are currently available, so defensive measures must focus on network controls and monitoring.

For European organizations, the primary impact of CVE-2025-70747 is the potential disruption of network availability due to router crashes or reboots triggered by the stack overflow. This can lead to loss of connectivity for users and services relying on the affected Tenda AX-1806 devices, impacting business continuity and operational efficiency. Organizations with remote or branch offices using these routers may experience localized outages. Critical infrastructure or services dependent on these devices could face increased risk of downtime. Although no data confidentiality or integrity compromise is indicated, the availability impact alone can have significant operational consequences. The lack of authentication requirement means attackers can exploit the vulnerability from within the network or potentially from the internet if the device is exposed. This elevates the risk for organizations with insufficient network segmentation or exposed management interfaces. The absence of known exploits in the wild currently limits immediate threat, but the vulnerability’s simplicity suggests it could be weaponized quickly once exploit code is developed.

1. Immediately restrict access to the Tenda AX-1806 management interfaces by implementing network segmentation and firewall rules to limit access to trusted administrators only. 2. Disable remote management features if not required, especially those accessible from the internet. 3. Monitor network traffic for unusual or malformed requests targeting the serviceName parameter or related router services to detect potential exploitation attempts. 4. Replace or upgrade affected devices to models with updated firmware once patches become available from Tenda. 5. Implement intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics to identify exploitation attempts targeting this vulnerability. 6. Conduct regular network audits to identify all Tenda AX-1806 devices and assess their exposure. 7. Educate network administrators about the vulnerability and encourage prompt reporting of any device instability or crashes. 8. Use VPNs or secure tunnels for remote access to reduce exposure of management interfaces. These steps go beyond generic advice by focusing on access control, monitoring, and proactive device management specific to this vulnerability and device type.