A critical stack-based buffer overflow in the Tenda F456 router, version 1.0.0.5, poses a significant risk of remote code execution for authenticated users.

The vulnerability exists within the fromP2pListFilter function of the /goform/P2pListFilter endpoint. An authenticated attacker can trigger a stack-based buffer overflow by providing an excessively long string to the page parameter, as the application fails to perform adequate length validation before passing the input to the sprintf function.

Successful exploitation of this flaw allows an attacker to achieve remote code execution on the affected device, potentially leading to a full compromise of the router. Given the CVSS score of 8.8, this vulnerability is classified as High, indicating a severe risk to network integrity. Compromise of network infrastructure can facilitate lateral movement within the environment, data interception, and total loss of device control.

Immediate Action: Since a vendor-provided patch is currently unknown, administrators should restrict access to the web management interface and ensure that only trusted users have authenticated access to the device.

Proactive Monitoring: Monitor network traffic for unusual POST requests directed at the /goform/P2pListFilter endpoint and review system logs for signs of service crashes or unauthorized configuration changes.

Compensating Controls: Implement a Web Application Firewall or network-level access control lists to prevent unauthorized or suspicious traffic from reaching the device management interface.

Public Exploit Available: Yes, a published proof-of-concept exists and is attributed to the technical write-up provided in the vulnerability references.

Given the availability of a public proof-of-concept and the high CVSS severity, this vulnerability presents a credible threat to the Tenda F456 router. Organizations should prioritize restricting administrative access to the device and monitor for any vendor announcements regarding a firmware update. Until a formal patch is released, the device should be considered at risk of compromise if exposed to untrusted network segments.