Microsoft has released a fix for a Windows Defender zero-day called RoguePlanet that could let attackers gain full SYSTEM-level control on Windows 10 and Windows 11 devices. The flaw is tracked as CVE-2026-50656 and was publicly disclosed with proof-of-concept code by the researcher using the handle Nightmare Eclipse after June 2026 Patch Tuesday. Microsoft says the issue is fixed in Microsoft Malware Protection Engine version 1.1.26060.3008, the scanning engine used by Defender and related security products.
Why it matters: This affects widely used built-in Windows security software on fully patched consumer and enterprise systems, so defenders should verify the updated Malware Protection Engine version is installed as soon as possible. Public exploit code exists, which raises the risk of copycat abuse even if exploitation is unreliable.
2026.07.09
97% relevant
This article is a direct update on the same RoguePlanet event, adding that Microsoft has now fixed CVE-2026-50656 via a Microsoft Malware Protection Engine update rather than Patch Tuesday and advising customers to run the latest engine version.
Eduard Kovacs
2026.07.09
97% relevant
This article directly updates the same event by reporting that Microsoft has now rolled out the fix for RoguePlanet via a Microsoft Malware Protection Engine update, after the zero-day exploit was published and after Microsoft's earlier advisory.
info@thehackernews.com (The Hacker News)
2026.07.09
99% relevant
This article covers the same underlying event: Microsoft releasing a fix for the RoguePlanet Windows Defender zero-day, tracked as CVE-2026-50656, which can be exploited to gain SYSTEM privileges on Windows 10 and 11.
Sergiu Gatlan
2026.07.09
100% relevant
The article establishes a distinct new event: Microsoft has now shipped the patch for RoguePlanet, a specific Windows Defender zero-day tracked as CVE-2026-50656, rather than only discussing public disclosure of other Nightmare Eclipse flaws.
← Back to all stories