CVE-2025-49678
📋 TL;DR
This vulnerability is a null pointer dereference in Windows NTFS that allows an authenticated attacker to execute arbitrary code with elevated privileges on the local system. It affects Windows systems with NTFS file systems. Attackers need local access to exploit this flaw.
💻 Affected Systems
- 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 compromise with SYSTEM privileges, enabling installation of persistent malware, data theft, and lateral movement across the network.
Likely Case
Local privilege escalation allowing attackers to bypass security controls, install additional tools, and access sensitive system resources.
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
Requires local authenticated access. Exploitation involves triggering specific NTFS operations to cause null pointer dereference.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: To be determined from Microsoft Security Update
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49678
Restart Required: Yes
Instructions:
1. Check Microsoft Security Update for CVE-2025-49678. 2. Apply the appropriate Windows security update. 3. Restart the system as required.
🔧 Temporary Workarounds
Restrict local access
windowsLimit local user access to systems through proper access controls and monitoring
Enable exploit protection
windowsUse Windows Defender Exploit Guard or similar endpoint protection to detect privilege escalation attempts
🧯 If You Can't Patch
- Implement strict least privilege principles for all user accounts
- Deploy endpoint detection and response (EDR) solutions to monitor for privilege escalation behavior
🔍 How to Verify
Check if Vulnerable:
Check Windows version and compare with Microsoft's affected versions list for CVE-2025-49678Check Version:
wmic os get caption, version, buildnumberVerify Fix Applied:
Verify Windows Update history shows the security update for CVE-2025-49678 has been installed📡 Detection & Monitoring
Log Indicators:
- Unexpected privilege escalation events in Windows Security logs
- Process creation with SYSTEM privileges from non-admin users
Network Indicators:
- Lateral movement attempts following local privilege escalation
SIEM Query:
EventID=4688 AND NewProcessName CONTAINS 'cmd.exe' AND SubjectUserName NOT IN (admin_users) AND TokenElevationType=2