Netis WF2780 Null Pointer Dereference Vulnerability in cgitest.cgi Allowing Denial-of-Service

A null pointer dereference vulnerability has been identified in the Netis WF2780 router, specifically in the firmware version 2.2.35445. The issue arises in the FUN_0048a728 function within the cgitest.cgi file. Attackers can exploit this vulnerability by manipulating the CONTENT_LENGTH environment variable, leading to a program crash and causing a denial-of-service (DoS) condition.

Impact

Exploitation of this vulnerability causes a null pointer dereference, leading to a program crash and a denial-of-service condition.

Reproduction

The vulnerability can be reproduced by setting the CONTENT_LENGTH environment variable to a negative value, which triggers the null pointer dereference in the cgitest.cgi file.