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Microsoft Patch Tuesday December 2025 Addresses Actively Exploited Zero-Days

patch Tuesdayzero-daysecurity updateimportant vulnerabilitiescritical vulnerabilitiesexploitprivilege escalationMicrosoftthreat mitigationpatchscript-based attacksactively exploitedCVEremote code executionvulnerability
Updated December 10, 2025 at 11:03 PM2 sources

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Microsoft released its December 2025 Patch Tuesday updates, addressing 57 security vulnerabilities across Windows 10, Windows 11, Windows Server, Office, and related services. Among these, three zero-day vulnerabilities were highlighted: CVE-2025-62221, an actively exploited privilege escalation flaw in the Windows Cloud Files Mini Filter Driver; CVE-2025-64671, a remote code execution vulnerability in GitHub Copilot for JetBrains; and CVE-2025-54100, a remote code execution issue in Windows PowerShell. The update also introduced a new warning in PowerShell to alert users when the Invoke-WebRequest command fetches web pages without safe parameters, aiming to prevent script-based attacks that exploit unsafe web content retrieval.

Throughout 2025, Microsoft addressed a total of 1,130 CVEs via Patch Tuesday releases, with 41 zero-day vulnerabilities patched, including 24 that were exploited in the wild. Elevation of Privilege and Remote Code Execution vulnerabilities made up the majority of the year's patches, reflecting ongoing attacker focus on these vectors. The December update continues Microsoft's trend of prioritizing critical and important vulnerabilities, reinforcing the need for organizations to promptly apply security updates to mitigate active threats.

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