RedSun: How Windows Defender's Remediation Became a SYSTEM File Write
2026-04-16A technical teardown of the RedSun zero-day — the second Defender escalation in two weeks from the same researcher — grounded in the actual source code.
I write about systems that fail in interesting ways — vulnerability classes, broken trust models, cryptographic assumptions that turned out to be wrong, and occasionally the institutional dynamics that keep bad designs alive longer than they should be.
I've been in the hash-and-trust business since before most CVE programs existed.
A technical teardown of the RedSun zero-day — the second Defender escalation in two weeks from the same researcher — grounded in the actual source code.
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