Executive Risk Summary
"A heap-based buffer overflow vulnerability in the Windows Cloud Files Mini Filter Driver allows an authorized attacker to elevate privileges locally, potentially leading to unauthorized access to sensitive data and system compromise. This vulnerability requires an attacker to have valid credentials on the system, but could still have significant impact due to the potential for privilege escalation."
Operational Audit Arsenal
Target Type Driver
Target Asset wcifs.sys
Standard Path %windir%System32drivers
PowerShell
# 🛠️ Senior Engineer Universal Audit
# Target: wcifs.sys (Driver)
$Targets = 'wcifs.sys'
$SearchPaths = @("$env:windir\System32", "$env:ProgramFiles", "${env:ProgramFiles(x86)}")
Get-ChildItem -Path $SearchPaths -Include $Targets -Recurse -ErrorAction SilentlyContinue |
Select-Object FullName, @{Name="Version";Expression={$_.VersionInfo.ProductVersion}}Patch Impact Forecast
Reboot Required Likely
Moderate, as the patch may require a system restart and could potentially impact cloud file access
Internal Work Notes
CVE-2026-20940: Windows Cloud Files Mini Filter Driver vulnerability allowing local privilege escalation; patching required to prevent potential unauthorized access and system compromise. PowerShell audit script: Get-Module -ListAvailable | Where-Object {$_.Name -eq 'wcifs'} | ForEach-Object {Get-ChildItem -Path $_.Path}
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Intelligence Sources
Related Microsoft Threats
Data compiled from NVD, MSRC, and CISA KEV Catalog. Intelligence synthesized via AI. Scripts provided for diagnostic purposes under MIT License.