Tenda A15 WiFi extenders are vulnerable to a critical remote code execution flaw due to a buffer overflow in the configuration upload function.

A stack-based buffer overflow exists in the UploadCfg function within the /cgi-bin/UploadCfg file. A remote, unauthenticated attacker can manipulate the File argument to overflow the stack and gain control of the device.

Successful exploitation allows an attacker to gain full control over the Tenda A15 device. This can lead to the interception of network traffic, redirection of users to malicious websites (DNS hijacking), and use of the device as a pivot point for further attacks on the internal network. The CVSS score of 9.8 underscores the critical nature of this hardware vulnerability.

Immediate Action: Update the Tenda A15 firmware to the latest version provided by the vendor. If no patch is available, consider replacing the device.

Proactive Monitoring: Monitor for unusual outbound traffic from the device and review administrative logs for unauthorized configuration changes.

Compensating Controls: Disable the web management interface from being accessible over the WAN and ensure the device is behind a robust network firewall.

Public Exploit Available: true

The public availability of an exploit for a CVSS 9.8 vulnerability makes this a critical priority. Administrators should apply the vendor-supplied firmware update immediately or decommission the affected hardware to prevent network compromise.