UTT HiPER 840G Buffer Overflow Vulnerability in FormTaskEdit

A buffer overflow vulnerability has been identified in the UTT HiPER 840G router, affecting firmware versions through 3.1.1-190328. The issue arises in the '/goform/formTaskEdit' endpoint, where the 'txtMin2' parameter can be manipulated to cause a buffer overflow. This vulnerability allows for remote exploitation, and a public proof-of-concept exploit is available.

Impact

Exploitation of this vulnerability leads to a buffer overflow, which can commonly result in arbitrary code execution or causing a denial-of-service condition on the device.

Reproduction

The vulnerability can be reproduced by sending a POST request to the '/goform/formTaskEdit' endpoint. The request must include a 'txtMin2' parameter with a payload that exceeds the buffer size, effectively causing the overflow. This can be done by manipulating the 'selDateType' parameter to bypass certain checks, allowing the 'txtMin2' parameter to be exploited.