Mercury D196G Buffer Overflow Vulnerability in fac_password Parameter

A buffer overflow vulnerability has been identified in the Mercury D196G device, specifically in the firmware version d196gv1-cn-up_2020-01-09_11.21.44. The issue arises in the function sub_404CAEDC, where the parameter fac_password is handled without proper validation. This vulnerability can be exploited by sending a crafted HTTP request, leading to a denial-of-service condition where the device crashes.

Impact

Exploitation of this vulnerability causes the device to crash, creating a denial-of-service condition.

Reproduction

The vulnerability can be reproduced by sending a POST request to the device's web interface. The request must include a JSON payload that specifies a password for the 'fac_password' parameter, deliberately crafted to overflow the buffer. This can be done using a Python script that utilizes the 'requests' library to automate the process.