Microsoft Defender Patch Bypass: High Severity Zero-Day Privilege Escalation (CVE-2026-50656/RoguePlanet, ShieldBreak)
Brief
Threat Summary A critical zero-day vulnerability (CVE-2026-50656/“RoguePlanet”) in Microsoft Defender’s Malware Protection Engine (mpengine. dll) enables local users, including standard, low-privilege accounts, to escalate privileges to NT AUTHORITY\SYSTEM using a race condition and improper link resolution. Microsoft initially issued a patch (Engine v1.
- 26060. 3008) in July 2026.
However, on August 12, 2026, a new exploit chain, “ShieldBreak,” … Microsoft Defender Patch Bypass: High Severity Zero-Day Privilege Escalation (CVE-2026-50656/RoguePlanet, ShieldBreak)
Microsoft Defender Patch Bypass: High Severity Zero-Day Privilege Escalation (CVE-2026-50656/RoguePlanet, ShieldBreak) - Arctic Wolf