regchulaGGcaptcha.js

// ==UserScript==
// @name        Reg Chula
// @namespace   sssss
// @description wtf
// @include     https://www2.reg.chula.ac.th/cu/reg/logon/logonframe.html
// @version     1
// @grant       none
// ==/UserScript==
document.body.onload = function() {
  document.getElementsByTagName('frame')[2].contentDocument.getElementsByName('code')[0].parentNode.innerHTML += "<button id='autoCap'>AUTO CAPTCHA !!!</button>";
  document.getElementsByTagName('frame')[2].contentDocument.getElementById('autoCap').onclick = fillCaptcha;
}
function fillCaptcha(t) {
    flag = ""
    for(var i of document.getElementsByTagName('frame')[2].contentDocument.getElementsByTagName('img')) 
    { 
      atr = i.getAttribute('src'); 
      if(atr.indexOf('/random/')!=-1) 
        flag += ("BA9876543210ZYXWVUTSRQPONMLKJIHGFEDCBA9876543210DCYXWVUTSRQPONMLKJIHZGFEDCBA9876543210YXWVUTSRQPONMLKJIHGFE"[parseInt(atr.substring(40,atr.lastIndexOf('.')))]) 
    }
    //alert(flag);
  console.log("REKT CHULA !!!",flag)
    document.getElementsByTagName('frame')[2].contentDocument.getElementsByName('code')[0].value = flag;
  }