ShieldBreak: New Windows Zero-Day Bypasses Microsoft’s RoguePlanet Patch
Brief
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 a PoC for ShieldBreak, a Microsoft Defender zero-day. The flaw bypasses the patch for CVE-2026-50656 ( RoguePlanet ), a race condition that can allow attackers to spawn a SYSTEM-level shell.
Successful exploitation could enable arbitrary code execution and other unauthorized actions on affected Windows systems.
“Microsoft has failed to properly patch the RoguePlanet vulnerability CVE-2026-50656, this PoC demonstrates a full patch bypass.” said Chaotic Eclipse . “The PoC was tested in the latest version of windows 11 25h2 (+Canary channel) and windows server 2025, the PoC also have a 100% success rate.