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Nightmare-Eclipse Drops Another Windows Defender Zero-Day, RoguePlanet

Written by Content Team | Jun 11, 2026 12:22:23 PM

A researcher known as Nightmare-Eclipse has released yet another Microsoft zero-day exploit — this one called RoguePlanet — timed to drop right after Microsoft's June Patch Tuesday, which addressed a record 206 CVEs.

The new exploit targets Windows Defender via a race condition, potentially granting attackers full SYSTEM-level access on Windows 10 and 11. It's the latest salvo in a months-long feud that began in April with the BlueHammer exploit. Microsoft has since patched several of Nightmare-Eclipse's disclosures, but real-world exploitation has already occurred.

The researcher claims to have more vulnerabilities in Defender and other Windows components ready to go.

Source: Dark Reading