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CRITICAL: THIS VULNERABILITY IS ACTIVELY BEING EXPLOITED IN THE WILD (CISA KEV CATALOG)
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CVE-2025-21418

Exploited

Windows - Ancillary Function Driver for WinSock

Microsoft CVSS 7.8 Updated March 10, 2026

Executive Risk Summary

"A vulnerability in the Windows Ancillary Function Driver for WinSock could allow an attacker to elevate privileges. This vulnerability is considered critical and has been added to the Known Exploited Vulnerabilities Catalog by CISA."

Operational Audit Arsenal

Target Type Driver
Target Asset afd.sys
Standard Path %windir%\System32\drivers
PowerShell
# 🛠️ Senior Engineer Universal Audit
# Target: afd.sys (Driver)
$Targets = 'afd.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

Network services may be affected

Internal Work Notes

Elevation of Privilege vulnerability in Windows Ancillary Function Driver for WinSock, patching required to prevent potential exploitation.

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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.