CRITICALZero Day
Global

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

·Source: The Hacker News

Updated:

Executive Summary

Microsoft has formally disclosed that it's working to release a patch to address a Defender zero-day codenamed RoguePlanet. The vulnerability has now been assigned the CVE identifier CVE-2026-50656 (CVSS score: 7.8), with the tech giant describing it as a privilege escalation flaw. "Microsoft is aware of an elevation of privilege in the Microsoft Malware Protection Engine in Microsoft Defender

Analysis

Microsoft has formally disclosed that it's working to release a patch to address a Defender zero-day codenamed RoguePlanet. The vulnerability has now been assigned the CVE identifier CVE-2026-50656 (CVSS score: 7.8), with the tech giant describing it as a privilege escalation flaw. "Microsoft is aware of an elevation of privilege in the Microsoft Malware Protection Engine in Microsoft Defender

Indicators of Compromise (1)

CVE (1)
CVE-2026-50656
NVDMITRE CVE
Source Attribution

Originally published by The Hacker News on Jun 17, 2026.

Related Threats

CRITICALZero DayPOC

CVE-2026-69414 ShieldBreak Zero-Day: No Patch, and CISA BOD 26-04 Gives You 14 Days

Executive Summary ShieldBreak (CVE-2026-69414) is a zero-day elevation-of-privilege vulnerability in the Microsoft Malware Protection Engine used by Microsoft Defender, allowing a low-privilege local attacker to escalate to SYSTEM. A public PoC was released on August 12, 2026, and Microsoft assigned the CVE on August 14, and no patch is available yet. Qualys VMDR provides detection […]

CVE-2026-69414CVE-2026-50656
Qualys Blog
CRITICALRansomware

Researcher creates workaround for Microsoft Defender security patch

Just weeks after Microsoft patched a critical hole in Microsoft Defender, a cybersecurity researcher has posted an apparent workaround that provides system-level control to attackers once they gain any level of access. The researcher, who goes by the name Nightmare Eclipse, has been engaged in a long-running battle with Microsoft Security . As of publication time, neither Microsoft nor Nightmare E

CVE-2026-50656
CSO Online
CRITICALRansomware

Researcher bypasses Microsoft Defender security patch, seizing control

Just weeks after Microsoft patched a critical hole in Microsoft Defender, a cybersecurity researcher has posted an apparent bypass that provides system-level control to attackers once they gain any level of access. The researcher, who goes by the name Nightmare Eclipse, has been engaged in a long-running battle with Microsoft Security . Nightmare Eclipse has not provided the further details we req

CVE-2026-50656
CSO Online