restore overridden window.JSON object

Question

Some code that I don\'t have control over is overriding the global JSON object without checking if it\'s already implemented:

var JSON = {
  org: \"http://ww         


        

Answer 1

You can create an iframe element (which will load about:blank and hence create a new context) and get a JSON object from there.

function restoreJSON() {
  var f = document.createElement("iframe");
  f.style.display = "none";
  document.documentElement.appendChild(f);
  window.JSON = f.contentWindow.JSON;
  document.documentElement.removeChild(f);
}

about:blank is loaded synchronously, so no need to wait for the load event. While this isn't restoring the original JSON object, it is getting one black-box identical to it.