CVE-2025-62217
📋 TL;DR
A race condition vulnerability in Windows Ancillary Function Driver for WinSock allows authenticated attackers to execute code with elevated privileges. This affects Windows systems where an attacker already has some level of access. The vulnerability enables local privilege escalation from a lower-privileged account to SYSTEM-level access.
💻 Affected Systems
- Microsoft Windows
📦 What is this software?
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 23h2 by Microsoft
Windows 11 24h2 by Microsoft
Windows 11 25h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM privileges, enabling installation of persistent malware, credential theft, and lateral movement across the network.
Likely Case
Local privilege escalation allowing attackers to bypass security controls, install additional tools, and maintain persistence on compromised systems.
If Mitigated
Limited impact if proper access controls, least privilege principles, and endpoint protection are in place to detect and block privilege escalation attempts.
🎯 Exploit Status
Race conditions typically require precise timing and may be less reliable than other exploitation methods. Requires authenticated access to the target system.
🛠️ 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-2025-62217
Restart Required: Yes
Instructions:
1. Open Windows Update Settings
2. Click 'Check for updates'
3. Install all available security updates
4. Restart the system when prompted
🔧 Temporary Workarounds
Restrict user privileges
windowsImplement least privilege principle to limit potential impact
Enable exploit protection
windowsUse Windows Defender Exploit Guard to mitigate privilege escalation attempts
🧯 If You Can't Patch
- Implement strict access controls and monitor for privilege escalation attempts
- Deploy endpoint detection and response (EDR) solutions to detect exploitation behavior
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for the specific security update or use Microsoft's Security Update GuideCheck Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify the security update is installed via Windows Update history or systeminfo command📡 Detection & Monitoring
Log Indicators:
- Unusual process creation with SYSTEM privileges
- Suspicious driver loading or modification
- Failed privilege escalation attempts in security logs
Network Indicators:
- Lateral movement following local privilege escalation
- Unusual outbound connections from previously low-privileged accounts
SIEM Query:
EventID=4688 AND NewProcessName CONTAINS 'cmd.exe' OR 'powershell.exe' AND SubjectUserName != SYSTEM AND TokenElevationType != %%1936