A critical buffer overflow vulnerability in Tenda CH22 allows remote attackers to execute code or cause system crashes, posing a significant risk to device integrity.

The vulnerability is a buffer overflow (CWE-120) located in the fromwebExcptypemanFilter function of the /goform/webExcptypemanFilter endpoint. Attackers with low-level privileges can trigger this memory corruption by providing a manipulated value to the page argument.

Successful exploitation of this buffer overflow can lead to a complete compromise of the affected Tenda device, potentially allowing for remote code execution or persistent service denial. Given the CVSS score of 8.8, this vulnerability represents a high risk of unauthorized system access, which could be leveraged to gain entry into the local network environment.

Immediate Action: Contact Tenda support or check the official vendor website to determine if a firmware update is available for this specific model. If no patch is currently available, isolate the device from external network access immediately.

Proactive Monitoring: Review system and firewall logs for unusual traffic patterns targeting the /goform/webExcptypemanFilter endpoint. Monitor device performance for unexpected reboots or degradation that may indicate exploitation attempts.

Compensating Controls: Deploy a Web Application Firewall or router-level access control list to restrict access to the web management interface to known, trusted administrative IP addresses only.

Public Exploit Available: Yes — a published proof-of-concept exists on GitHub as referenced in the vulnerability report at https://github.com/QIU-DIE/CVE/issues/22.

Due to the presence of a public proof-of-concept and the potential for remote code execution, this vulnerability poses a severe threat to network security. Administrators should prioritize restricting administrative access to the affected devices immediately and monitor vendor communications closely for the release of a corrective firmware patch.