AI synthesis Chaotic Eclipse released a PoC for ShieldBreak, a Microsoft Defender zero-day bypassing the CVE-2026-50656 patch to achieve SYSTEM-level code execution. The vulnerability highlights an incomplete fix in Defender for Windows.
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The security researcher going by the name Chaotic Eclipse (aka INFINITE NIGHTMARE, MSNightmare, and Nightmare-Eclipse) has released a proof-of-concept (PoC) for a new Microsoft zero-day called ShieldBreak. The vulnerability, rooted in Microsoft Defender for Windows, demonstrat...
Chaotic Eclipse released a PoC for ShieldBreak, a Microsoft Defender zero-day that bypasses the CVE-2026-50656 patch and could enable SYSTEM-level code execution. Security researcher Chaotic Eclipse, also known as INFINITE NIGHTMARE, MSNightmare and Nightmare-Eclipse, released...
Nightmare Eclipse has released a new Microsoft Defender zero-day exploit named "ShieldBreak" after Microsoft released the August 2026 Patch Tuesday security updates. [...]
Dropped on Patch Tuesday, the exploit allows any user to spawn a shell with System privileges. The post Nightmare Eclipse Drops Windows Zero-Day Exploit ‘ShieldBreak’ appeared first on SecurityWeek.