ProtectCyber
Back to Insights
Secure Software2 min readApril 16, 2026

New Microsoft Defender “RedSun” zero-day PoC grants SYSTEM privileges

A security researcher has publicly released an exploit for a zero-day vulnerability in Microsoft Defender that allows attackers to gain SYSTEM-level privileges on Windows systems. You should immediately prioritize patching Microsoft Defender and monitor y

Could your website be vulnerable to attacks like this?

Run a free 10-point security scan on your site — headers, SSL, DNS, and more. Results in 15 seconds.

Test Your Site Now — It's Free