CVE-2025-49667
📋 TL;DR
This vulnerability involves a double-free memory corruption flaw in the Windows Win32K ICOMP component, allowing authenticated attackers to escalate privileges locally. It affects Windows systems where an attacker already has some level of access and can execute code. Successful exploitation could lead to complete system compromise.
💻 Affected Systems
- Microsoft Windows
📦 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 takeover with SYSTEM/administrator privileges, enabling installation of persistent malware, data theft, and lateral movement across the network.
Likely Case
Local privilege escalation from standard user to administrator/SYSTEM level, allowing attackers to bypass security controls and maintain persistence.
If Mitigated
Limited impact if proper privilege separation, application control, and endpoint protection are in place to detect and block exploitation attempts.
🎯 Exploit Status
Exploitation requires authenticated access and knowledge of memory corruption techniques. Double-free vulnerabilities can be challenging to exploit reliably but are often weaponized once stable exploits are developed.
🛠️ 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-2025-49667
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 local user privileges
windowsLimit standard users to minimal required privileges to reduce attack surface
Enable Windows Defender Exploit Guard
windowsConfigure exploit protection to mitigate memory corruption attacks
🧯 If You Can't Patch
- Implement strict application control policies to prevent unauthorized code execution
- Deploy endpoint detection and response (EDR) solutions with memory protection capabilities
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for missing security patches or use Microsoft's Security Update GuideCheck Version:
wmic os get caption, version, buildnumber, csdversionVerify Fix Applied:
Verify the latest Windows security updates are installed and system has been restarted📡 Detection & Monitoring
Log Indicators:
- Unusual process creation with elevated privileges
- Suspicious Win32K API calls
- Memory corruption events in Windows Event Logs
Network Indicators:
- Lateral movement attempts following local privilege escalation
SIEM Query:
EventID=4688 AND NewProcessName LIKE '%cmd.exe%' OR '%powershell.exe%' AND SubjectUserName!=SYSTEM AND TokenElevationType=%%1938