Researcher Drops BigDiskBuster Zero-Day PoC That Blocks Microsoft Defender Updates

A researcher has released a zero-day proof-of-concept tool called BigDiskBuster that can prevent Microsoft Defender from installing updates by consuming all available disk space. The tool was published on GitHub and currently has no patch or official advisory from Microsoft. BigDiskBuster's author is Abdelhamid Naceri, a former Microsoft security researcher who has previously developed Defender exploits. Naceri made the tool available on September 19. The absence of a patch or CVE assignment leaves Microsoft Defender users without a fix for this issue. The tool's release may pose a problem for users relying on Microsoft Defender for security updates.