CVE-2025-21391, the zero-day Windows storage flaw, stems from the way Windows resolves file paths and follows links, Walters said. File deletion is just the beginning of the problems it could cause, as it could lead to privilege escalation, unwanted access to security logs or configurations, malware injection, data manipulation, or other attacks.

Redmond has made some certificate-handling changes that could trip unprepared admins Patch Tuesday Microsoft’s February patch collection is mercifully smaller than January’s mega-dump. But don't get too relaxed – some deserve close attention,