CVE-2025-47971
📋 TL;DR
A buffer over-read vulnerability in Virtual Hard Disk (VHDX) handling allows local attackers to read beyond allocated memory boundaries. This can lead to privilege escalation by exposing sensitive information or causing system instability. Affects systems using VHDX virtual disk files, primarily Windows environments with virtualization components.
💻 Affected Systems
- Microsoft Windows
- Hyper-V
- Windows Server
📦 What is this software?
Windows 10 1507 by Microsoft
Windows 10 1507 by Microsoft
Windows 10 1607 by Microsoft
Windows 10 1607 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 1809 by Microsoft
Windows 10 21h2 by Microsoft
Windows 10 22h2 by Microsoft
Windows 11 22h2 by Microsoft
Windows 11 23h2 by Microsoft
Windows 11 24h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through privilege escalation to SYSTEM/root, allowing attacker to install persistent malware, access all data, and control the entire system.
Likely Case
Local privilege escalation from standard user to administrator privileges, enabling lateral movement, credential theft, and persistence establishment.
If Mitigated
Limited information disclosure or system crash without privilege escalation if proper memory protections are enabled.
🎯 Exploit Status
Requires local access and ability to interact with VHDX files. Exploitation likely involves crafted VHDX files.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific KB numbers
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-47971
Restart Required: Yes
Instructions:
1. Apply latest Windows security updates via Windows Update. 2. For enterprise: Deploy through WSUS or Microsoft Endpoint Configuration Manager. 3. Verify update installation with system restart.
🔧 Temporary Workarounds
Restrict VHDX file access
windowsLimit who can create or modify VHDX files to reduce attack surface
icacls *.vhdx /deny Users:(R,W,X)
Set file permissions to restrict VHDX file access to administrators only
Disable unnecessary virtualization features
windowsTurn off Hyper-V or virtualization components if not required
Disable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V
dism.exe /Online /Disable-Feature:Microsoft-Hyper-V
🧯 If You Can't Patch
- Implement strict access controls on VHDX files and virtualization components
- Deploy application control policies to prevent execution of unauthorized programs that could exploit this vulnerability
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for missing security updates related to CVE-2025-47971Check Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify KB update is installed via 'Get-Hotfix' in PowerShell or 'systeminfo' command📡 Detection & Monitoring
Log Indicators:
- Event ID 1000 application crashes related to vhdmp.sys or storvsp.sys
- Unexpected process creation with SYSTEM privileges from user accounts
- Access to VHDX files from non-admin accounts
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
EventID=1000 AND (SourceName="Application Error" OR SourceName="Windows Error Reporting") AND (Message="*vhdmp.sys*" OR Message="*storvsp.sys*")