CVE-2025-48818
📋 TL;DR
A Time-of-Check Time-of-Use (TOCTOU) race condition vulnerability in Windows BitLocker allows an attacker with physical access to bypass security features and potentially access encrypted data. This affects Windows systems using BitLocker encryption. The vulnerability requires physical access to the target system.
💻 Affected Systems
- Windows BitLocker
📦 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
An attacker with physical access could bypass BitLocker encryption entirely, gaining unauthorized access to encrypted data on stolen or unattended devices.
Likely Case
Targeted physical attacks against specific high-value devices to bypass disk encryption protections.
If Mitigated
With proper physical security controls and device management, the risk is significantly reduced as physical access is required.
🎯 Exploit Status
Exploitation requires physical access and precise timing to trigger the race condition. No public exploit code available yet.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific patch versions
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-48818
Restart Required: Yes
Instructions:
1. Check Microsoft Security Update Guide for affected Windows versions. 2. Apply the latest Windows security updates from Microsoft. 3. Restart the system to complete the update.
🔧 Temporary Workarounds
Enhanced Physical Security
allImplement strict physical security controls to prevent unauthorized physical access to devices.
Device Management Controls
allEnsure devices are properly secured when unattended and implement device tracking/recovery solutions.
🧯 If You Can't Patch
- Implement strict physical security controls and device management policies
- Consider additional encryption layers or hardware security modules for critical data
🔍 How to Verify
Check if Vulnerable:
Check if BitLocker is enabled on Windows systems and verify Windows version against Microsoft's affected versions list.Check Version:
wmic os get caption, version, buildnumberVerify Fix Applied:
Verify Windows is updated to the patched version and confirm BitLocker is functioning normally.📡 Detection & Monitoring
Log Indicators:
- Multiple failed BitLocker unlock attempts
- Unexpected system restarts with BitLocker recovery
Network Indicators:
- None - this is a physical access vulnerability
SIEM Query:
Search for Event ID 24620 (BitLocker unlock failure) or unexpected BitLocker recovery events in Windows Security logs