CVE-2021-46393

Name of the Vulnerable Software and Affected Versions Tenda-AX3 router version V16.03.12.10 CN

Description The issue is related to a stack buffer overflow in the formSetPPTPServer function. The v10 variable is directly retrieved from the HTTP request parameter startIp without any security checks, leading to a stack overflow when sscanf is used. This can be exploited by sending a POST request to the /goform/SetPptpServerCfg API endpoint with a crafted startIp parameter, allowing for remote code execution.

Recommendations For Tenda-AX3 router version V16.03.12.10 CN, as a temporary workaround, consider disabling the formSetPPTPServer function until a patch is available. Restrict access to the /goform/SetPptpServerCfg API endpoint to minimize the risk of exploitation. Avoid using the startIp parameter in the affected API endpoint until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.