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#3 BleepingComputer general May 21, 2026 at 07:49 UTC

Microsoft warns of new Defender zero-days exploited in attacks

By Sergiu Gatlan

AI Summary

Microsoft began patching two actively exploited zero-day vulnerabilities in Microsoft Defender — tracked as affecting UnDefend and RedSun Defender components — that can be leveraged to elevate privileges to SYSTEM or trigger a denial-of-service condition. The flaws were confirmed as exploited in the wild prior to patch availability, making immediate patching critical for Windows environments.

Read full article → https://www.bleepingcomputer.com/news/security/mic…

Relevance score: 88.0/100

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