Microsoft Confirms RoguePlanet Zero-Day in Defender, Patch Under Development

Security Affairs

June 18, 2026 at 9:21 AM

CVE Zero-day Microsoft Vulnerability Patch Malware Privilege Escalation

Overview

Microsoft has confirmed a serious vulnerability in its Defender software, identified as the RoguePlanet zero-day (CVE-2026-50656), which has a CVSS score of 7.8. This flaw allows attackers to escalate privileges through the Microsoft Malware Protection Engine, potentially giving them greater access to affected systems. Microsoft is currently working on a security patch to address this issue but has not yet released specific details about the patch or when it will be available. Users of Microsoft Defender should remain vigilant and monitor for updates from Microsoft regarding this vulnerability, as it poses a significant risk to system security. The implications are serious, especially for organizations relying on Defender for malware protection.

Key Takeaways

Affected Systems: Microsoft Defender, Microsoft Malware Protection Engine.
Action Required: Microsoft is developing a patch to address this vulnerability; users should monitor for updates and apply patches as soon as they are released.
Timeline: Newly disclosed

Original Article Summary

Microsoft confirmed the RoguePlanet Defender zero-day (CVE-2026-50656), a privilege escalation flaw, and is developing a security patch. Microsoft has acknowledged the RoguePlanet zero-day affecting Microsoft Defender, tracked as CVE-2026-50656 (CVSS score of 7.8). The vulnerability allows privilege escalation through the Microsoft Malware Protection Engine. The company stated it is aware of the issue and is […]

Impact

Microsoft Defender, Microsoft Malware Protection Engine.

Exploitation Status

The exploitation status is currently unknown. Monitor vendor advisories and security bulletins for updates.

Timeline

Newly disclosed

Remediation

Microsoft is developing a patch to address this vulnerability; users should monitor for updates and apply patches as soon as they are released.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Zero-day, Microsoft, and 4 more.

Read Original Article

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