Tenda W20E Buffer Overflow Vulnerability in Guest Wifi Rule Management

A buffer overflow vulnerability has been identified in the Tenda W20E router, specifically in version V4.0br_V15.11.0.6. The issue arises in the 'goform/guestWifiRuleRefresh' component, where the sizes of the 'gstup' and 'gstdwn' parameters are not properly validated before being concatenated into 'gstruleQos'. This lack of validation can be exploited to cause a buffer overflow.

Impact

Exploitation of this vulnerability can lead to a buffer overflow, which may allow for arbitrary code execution or causing a denial-of-service condition on the device.