CVE-2025-62205
📋 TL;DR
A use-after-free vulnerability in Microsoft Office Word allows attackers to execute arbitrary code on a victim's system by tricking them into opening a malicious document. This affects users running vulnerable versions of Microsoft Word on Windows systems. Successful exploitation gives attackers the same privileges as the logged-in user.
💻 Affected Systems
- Microsoft Office Word
📦 What is this software?
365 Apps by Microsoft
365 Apps by Microsoft
Office Long Term Servicing Channel by Microsoft
View all CVEs affecting Office Long Term Servicing Channel →
Office Long Term Servicing Channel by Microsoft
View all CVEs affecting Office Long Term Servicing Channel →
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining the same privileges as the logged-in user, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Local code execution with user-level privileges, allowing attackers to steal documents, install malware, or move laterally within the network.
If Mitigated
Limited impact if proper application sandboxing, least privilege principles, and macro restrictions are in place, potentially containing the exploit to the Word process.
🎯 Exploit Status
Exploitation requires user interaction (opening a malicious document). The use-after-free vulnerability suggests reliable exploitation may require specific heap manipulation techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft's monthly security updates for Office
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-62205
Restart Required: Yes
Instructions:
1. Open any Office application
2. Go to File > Account > Update Options
3. Select 'Update Now'
4. Restart Office applications when prompted
5. Alternatively, use Windows Update for system-wide Office updates
🔧 Temporary Workarounds
Disable automatic document opening
windowsPrevent Office from automatically opening documents from untrusted sources
Set registry key: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Word\Security\FileValidation to 1
Enable Protected View
windowsForce documents from untrusted locations to open in Protected View
Set registry key: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Word\Security\ProtectedView to 1
🧯 If You Can't Patch
- Implement application allowlisting to restrict which Office versions can run
- Deploy Microsoft Attack Surface Reduction rules to block Office from creating child processes
🔍 How to Verify
Check if Vulnerable:
Check Office version in Word via File > Account > About Word and compare against patched versions in Microsoft advisoryCheck Version:
powershell Get-ItemProperty "HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\*" | Where-Object {$_.DisplayName -like "*Office*"} | Select-Object DisplayName, DisplayVersionVerify Fix Applied:
Verify Office update installation in Windows Update history or Office update status📡 Detection & Monitoring
Log Indicators:
- Word process spawning unexpected child processes
- Office application crashes with memory access violations
- Suspicious document opens from external sources
Network Indicators:
- Office applications making unexpected outbound connections after document open
- DNS queries to suspicious domains following document processing
SIEM Query:
source="windows" AND (process_name="WINWORD.EXE" AND (child_process_creation OR process_crash))