A critical buffer overflow vulnerability in Tenda AC23 routers allows remote attackers to achieve unauthorized memory corruption, posing a severe risk to device availability and integrity.

This is a memory corruption flaw resulting from a buffer overflow in the sscanf function within the /goform/SetStaticRouteCfg file. The vulnerability is triggered by sending a specially crafted argument list to the affected endpoint, which can be executed by an authenticated user.

Successful exploitation of this vulnerability allows an attacker to cause a denial of service or potentially execute arbitrary code on the affected router. Given the CVSS score of 8.8, this poses a high risk to network infrastructure, as the compromise of a gateway device can lead to unauthorized traffic interception, total loss of connectivity, or further lateral movement into the internal network.

Immediate Action: Since no official patch is currently identified, users should restrict access to the web management interface of the Tenda AC23 to trusted internal IP addresses only.

Proactive Monitoring: Monitor network traffic for unusual POST requests directed at the /goform/SetStaticRouteCfg endpoint and audit device logs for unexpected system reboots or service crashes.

Compensating Controls: Implement a Web Application Firewall (WAF) or network-level access control list (ACL) to block unauthorized access to the router management interface, effectively isolating the vulnerable function from external exposure.

Public Exploit Available: Yes, a published proof of concept exists via the referenced researcher writeup on GitHub.

Given the high CVSS severity and the availability of public technical details, administrators must treat this vulnerability with urgency. If firmware updates are not available from the vendor, immediate network segmentation and strict access controls are required to prevent unauthorized access to the management interface until a permanent fix is deployed.