Defender Patch Sparks Disk-Destroying Attack Scenario

Microsoft patched a Windows Defender zero-day (CVE-2026-50656), but researchers warn that new defense-in-depth changes connected to the Microsoft Malware Protection Engine and SpyNet could let an attacker exhaust disk space by writing massive data via a crafted SMB interaction. Exploitation would require a specialized SMB setup and a malicious file sequence; the fix is auto-installed, and the risk is currently described as a theoretical scenario amid tension between the researcher and Microsoft.