This story was originally published on HackerNoon at: https://hackernoon.com/the-browser-security-breakthrough-that-made-uaf-exploits-harder.
A deep dive into MemGC: how the Edge team eliminated Use-After-Free (UAF) vulnerabilities by turning a garbage collector into a hard security boundary.
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In the mid-2010s, Use-After-Free (UAF) vulnerabilities were the biggest security threat to Internet Explorer and Edge. To combat this, the team built MemGC, an architectural security boundary that brought Chakra's garbage collection directly into the DOM. By automating memory safety and abandoning manual cleanups, MemGC successfully eliminated an entire class of immediate UAF exploits. While it ultimately pushed attackers to pivot toward Type Confusion, it remains a great example of weaponizing computer science for systemic defense.