Full Report
Microsoft closed out 2025 with patches for 56 security flaws in various products across the Windows platform, including one vulnerability that has been actively exploited in the wild. Of the 56 flaws, three are rated Critical, and 53 are rated Important in severity. Two other defects are listed as publicly known at the time of the release. These include 29 privilege escalation, 18 remote code
Analysis Summary
# Vulnerability Summary: December 2025 Microsoft Patch Release (Focusing on Exploited/Zero-Day Flaws)
This summary focuses on the most critical and actively exploited vulnerabilities disclosed by Microsoft in their December 2025 update release, which addressed 56 flaws in total (3 Critical, 53 Important).
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## Vulnerability: Windows Cloud Files Mini Filter Driver Use-After-Free (Actively Exploited)
## CVE Details
- CVE ID: CVE-2025-62221
- CVSS Score: 7.8 (High/Important)
- CWE: Use-After-Free (Implied by technical description)
## Affected Systems
- Products: Windows operating system components utilizing the Cloud Files Mini Filter Driver (Used by OneDrive, Google Drive, iCloud, and present as a core Windows component).
- Versions: Any susceptible version of Windows (Specific versions not detailed in the summary text).
- Configurations: Requires the vulnerable driver to be present (which is standard for Windows).
## Vulnerability Description
This is a Use-After-Free vulnerability residing within the **Windows Cloud Files Mini Filter Driver**. Successful exploitation allows a locally authenticated attacker to achieve **privilege escalation to SYSTEM permissions** on the host machine.
## Exploitation
- Status: **Exploited in the wild**. Added to CISA's KEV catalog.
- Complexity: Medium/High (Requires prior access to the system via other means, such as phishing or RCE, to chain exploits).
- Attack Vector: Local (Requires initial access).
## Impact
- Confidentiality: Potentially High (Gaining SYSTEM access typically allows full data access).
- Integrity: High (SYSTEM permissions allow complete system modification).
- Availability: High (SYSTEM control allows for system destruction or persistent tampering).
## Remediation
### Patches
- CISA mandates Federal Civilian Executive Branch (FCEB) agencies apply the patch by **December 30, 2025**.
- The specific patch details are available in Microsoft's security update guide for December 2025.
### Workarounds
- No specific technical workarounds were mentioned in the context provided, beyond patching immediately.
## Detection
- **Indicator of Compromise (IoC):** Successful exploitation could lead to the deployment of kernel components or the abuse of signed drivers for persistence.
- **Detection Methods and Tools:** Monitoring for unusual privilege escalations, unauthorized driver loading, or attempts to exploit file system filter drivers are advised. MSTIC and MSRC credits suggest related telemetry data might be available through Microsoft security products.
## References
- Vendor Advisory: [msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-62221](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-62221) (Defanged)
- CISA KEV Catalog Listing: [cisa.gov/news-events/alerts/2025/12/09/cisa-adds-two-known-exploited-vulnerabilities-catalog](https://www.cisa.gov/news-events/alerts/2025/12/09/cisa-adds-two-known-exploited-vulnerabilities-catalog) (Defanged)
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## Vulnerability: Windows PowerShell Command Injection (Zero-Day)
## CVE Details
- CVE ID: CVE-2025-54100
- CVSS Score: 7.8 (High/Important)
- CWE: Command Injection (Implied)
## Affected Systems
- Products: Windows PowerShell
- Versions: Unspecified, affects versions processing web content.
- Configurations: Requires interaction with web content processed by PowerShell.
## Vulnerability Description
A command injection vulnerability exists in how Windows PowerShell processes web content. This allows an **unauthorized, unauthenticated attacker to execute code locally** if the vulnerable system interacts with malicious web content.
## Exploitation
- Status: **Publicly Known / Zero-Day**. (Implied to be actively targeted as part of the recent patch release alongside the exploited CVE).
- Complexity: Low to Medium (Depending on the specific path to trigger processing of malicious web content).
- Attack Vector: Network (Via specially crafted web content).
## Impact
- Confidentiality: High (Local Code Execution).
- Integrity: High (Local Code Execution).
- Availability: High (Local Code Execution).
## Remediation
### Patches
- Apply the December 2025 Microsoft Security Updates. Specific patch mapping is required via the official MSRC release notes.
### Workarounds
- Potential temporary mitigation could involve restricting PowerShell's interaction with external web content or blocking execution contexts known to be vulnerable, pending patch deployment.
## Detection
- Monitoring PowerShell execution patterns originating from web handling processes.
## References
- Vendor Advisory: [msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-54100](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-54100) (Defanged)
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## Vulnerability: GitHub Copilot for JetBrains Command Injection (Zero-Day)
## CVE Details
- CVE ID: CVE-2025-64671
- CVSS Score: 8.4 (High/Important)
- CWE: Command Injection (Implied)
## Affected Systems
- Products: GitHub Copilot for JetBrains IDEs (Requires installation of the extension within a JetBrains environment).
- Versions: Unspecified vulnerable versions.
- Configurations: Requires the GitHub Copilot extension to be installed and active.
## Vulnerability Description
A command injection flaw exists in GitHub Copilot for JetBrains, allowing an **unauthorized attacker to execute code locally** through manipulation of content processed by the extension.
## Exploitation
- Status: **Publicly Known / Zero-Day**.
- Complexity: Low to Medium.
- Attack Vector: Likely Network/Local (Dependent on how the extension processes input).
## Impact
- Confidentiality: High (Local Code Execution).
- Integrity: High (Local Code Execution).
- Availability: High (Local Code Execution).
## Remediation
### Patches
- Apply the December 2025 Microsoft/GitHub updates covering Copilot for JetBrains.
### Workarounds
- Temporarily disabling or removing the GitHub Copilot extension for JetBrains IDEs until the patch can be applied.
## References
- Vendor Advisory: [msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-64671](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-64671) (Defanged)
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*Note: The December release also included CVE-2025-62223 (Edge for iOS Spoofing, CVSS 4.3). While lower severity, it represents another specific addressable flaw.*