NightmareEclipse Strikes Again: BigDiskBuster Exploits Windows Defender Flaw

Security researcher NightmareEclipse has released another proof-of-concept tool to exploit vulnerabilities in Microsoft's Windows Defender antivirus software. The latest tool, dubbed BigDiskBuster, prevents Windows Defender from updating its security intelligence and platform versions.

According to NightmareEclipse, the tool works by creating temporary files that consume all available free space on the drive, causing the update process to fail. This leaves Windows Defender stuck on outdated security definitions, potentially leaving it unable to identify newly detected malware.

The researcher claims that BigDiskBuster is compatible with all supported versions of Windows, although this has not been independently verified. The tool does not disable Windows Defender entirely, but rather prevents it from updating its critical components.

BigDiskBuster is the latest in a series of proof-of-concept tools released by NightmareEclipse, who has been engaged in a public spat with Microsoft over the company's vulnerability disclosure process. Microsoft had previously criticized NightmareEclipse for releasing vulnerabilities without giving them a chance to fix them first.