Microsoft Confirms RoguePlanet Defender Zero-Day, Says Patch is in Development

Microsoft has acknowledged a zero-day privilege escalation vulnerability in the Microsoft Malware Protection Engine tracked as CVE-2026-50656 and nicknamed 'RoguePlanet'. A researcher released a public proof-of-concept that abuses a race condition to obtain a SYSTEM shell (CVSS 7.8); Microsoft is investigating and preparing a security update to address the flaw.