Key Findings Three Microsoft Defender zero-day vulnerabilities are being actively exploited in the wild by threat actors BlueHammer (CVE-2026-33825) has been patched as of April Patch Tuesday; RedSun and UnDefend remain unpatched All three flaws were released by researcher Chaotic Eclipse in response to Microsoft's vulnerability disclosure handling BlueHammer and RedSun enable local privilege escalation while UnDefend causes denial-of-service and blocks security definition up
