GHSA-RP9W-3FW7-7CWQ DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content

If the HTML you give it contains a element, and inside that template there's an element with a shadow DOM attached to it, DOMPurify quietly skips over the shadow contents. Whatever the attacker put in there - an image with an onerror handler, a link with a javascript: URL, even a full script -...