New BigDiskBuster Zero-Day Blocks Microsoft Defender Updates

• •BigDiskBuster blocks Microsoft Defender updates by filling disk space.
• •The vulnerability affects all supported Windows versions and has no patch yet.
• •Naceri has released multiple zero-day exploits since his dismissal from Microsoft.

Security researcher Abdelhamid Naceri, known as NightmareEclipse, released a proof-of-concept tool named BigDiskBuster that prevents Microsoft Defender from installing critical updates. This zero-day vulnerability affects all supported versions of Windows by filling disk space to block update processes. The tool does not disable Defender but keeps it from receiving the latest security intelligence and platform updates, leaving it vulnerable to new malware. As of now, there is no patch or CVE assigned to this vulnerability, and Microsoft has not confirmed its existence. Naceri has a history of releasing exploits against Microsoft products following his dismissal from the company. The tool is reported to be buggy and requires continuous operation to be effective. The release of this proof-of-concept raises concerns about potential exploitation by threat actors.