A remote buffer overflow vulnerability in Tenda CH22 firmware versions 1.0.0.1 poses a critical risk of complete system compromise.

This memory corruption flaw is caused by improper handling of the page argument within the fromNatStaticSetting function of the /goform/NatStaticSetting endpoint. The vulnerability is exploitable remotely by an authenticated user to achieve a buffer overflow.

The vulnerability carries a CVSS score of 8.8, reflecting its potential for total loss of system confidentiality, integrity, and availability. Successful exploitation allows an attacker to gain unauthorized control over network infrastructure, potentially leading to data interception, lateral movement within the local network, or complete denial of service.

Immediate Action: Since no official patch is currently identified, users should restrict administrative access to the device management interface to trusted internal networks only. Contact Tenda support or monitor their official website for the release of a firmware update addressing this specific buffer overflow.

Proactive Monitoring: Review device access logs for suspicious requests directed at the /goform/NatStaticSetting endpoint. Monitor network traffic for unusual payloads that may indicate attempts to trigger memory corruption.

Compensating Controls: Implement an access control list on the management interface to block external access. Deploy a network firewall to filter traffic and prevent unauthorized users from interacting with the vulnerable administrative endpoint.

Public Exploit Available: Yes, a published proof of concept exists as documented in the referenced GitHub repository.

Given the severity of this buffer overflow, immediate action is required to isolate the affected Tenda CH22 devices from public-facing exposure. While a vendor patch is pending, administrators must prioritize network-level restrictions to prevent potential exploitation. Continued vigilance and monitoring for firmware updates are essential to mitigating this risk permanently.