CVE-2024-21310
📋 TL;DR
This vulnerability in the Windows Cloud Files Mini Filter Driver allows an authenticated attacker to gain SYSTEM-level privileges on affected systems. It affects Windows 10, Windows 11, and Windows Server versions where the driver is present. Attackers need local access to exploit this privilege escalation flaw.
💻 Affected Systems
- Windows 10
- Windows 11
- Windows Server 2016
- Windows Server 2019
- Windows Server 2022
📦 What is this software?
Windows 10 1809 by Microsoft
Windows 10 21h2 by Microsoft
Windows 10 22h2 by Microsoft
Windows 11 21h2 by Microsoft
Windows 11 22h2 by Microsoft
Windows 11 23h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains full SYSTEM privileges, enabling complete system compromise, data theft, persistence establishment, and lateral movement across the network.
Likely Case
Local authenticated attacker elevates privileges to SYSTEM to install malware, disable security controls, or access protected resources.
If Mitigated
With proper access controls and least privilege principles, impact is limited to the compromised user account scope.
🎯 Exploit Status
Requires local authenticated access. Microsoft rates this as 'Exploitation More Likely' in their advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: February 2024 security updates (specific KB numbers vary by Windows version)
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21310
Restart Required: Yes
Instructions:
1. Apply February 2024 Windows security updates via Windows Update. 2. For enterprise: Deploy through WSUS, SCCM, or Microsoft Update Catalog. 3. Restart systems after patch installation.
🔧 Temporary Workarounds
Disable Cloud Files Mini Filter Driver
windowsTemporarily disable the vulnerable driver component (may impact cloud storage functionality)
fltmc unload cldflt
🧯 If You Can't Patch
- Implement strict least privilege access controls to limit local user privileges
- Monitor for privilege escalation attempts using EDR/SIEM tools
🔍 How to Verify
Check if Vulnerable:
Check if February 2024 security updates are installed via 'winver' or 'systeminfo' commandCheck Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify KB5022834 (Win10 21H2), KB5022838 (Win10 22H2), or corresponding February 2024 updates are installed📡 Detection & Monitoring
Log Indicators:
- Event ID 4697: Service installation attempts
- Unexpected SYSTEM privilege acquisition by non-admin users
- Driver loading events for cldflt.sys
Network Indicators:
- Unusual outbound connections following local privilege escalation
SIEM Query:
EventID=4697 OR (EventID=4688 AND NewProcessName LIKE '%cmd.exe%' AND SubjectUserName NOT IN ('SYSTEM', 'Administrator'))