Generic HTML Sanitizer Bypass Investigation (Patreon)

Generic HTML Sanitizer Bypass Investigation

I stumbled over a weird HTML behavior on Twitter and started to investigate it. Did I just stumble over a generic HTML Sanitizer bypass? Get my handwritten font https://shop.liveoverflow.com (advertisement) Checkout our courses on https://hextree.io (advertisement) The Tweet: https://twitter.com/MRCodedBrain/status/1662701541680136195 Google XSS: https://www.youtube.com/watch?v=lG7U3fuNw3A HTML Spec: https://html.spec.whatwg.org/multipage/parsing.html#parse-error-invalid-first-character-of-tag-name Chapters: 00:00 - Intro 01:09 - Sanitizing vs. Encoding 02:32 - Developing HTML Sanitizer Bypass 05:03 - Attacking DOMPurify 07:08 - Attacking Server-side Sanitizer 08:31 - HTML Parse Error Specification 10:08 - Potential Impact 11:55 - hextree.io =[ ❤️ Support ]= → per Video: https://www.patreon.com/join/liveoverflow → per Month: https://www.youtube.com/channel/UClcE-kVhqyiHCcjYwcpfj9w/join 2nd Channel: https://www.youtube.com/LiveUnderflow =[ 🐕 Social ]= → Twitter: https://twitter.com/LiveOverflow/ → Streaming: https://twitch.tvLiveOverflow/ → TikTok: https://www.tiktok.com/@liveoverflow_ → Instagram: https://instagram.com/LiveOverflow/ → Blog: https://liveoverflow.com/ → Subreddit: https://www.reddit.com/r/LiveOverflow/ → Facebook: https://www.facebook.com/LiveOverflow/