CVE-2025-54906
📋 TL;DR
This vulnerability in Microsoft Office involves a use-after-free memory corruption issue that allows an attacker to execute arbitrary code on a victim's system. Attackers can exploit this by tricking users into opening a malicious Office document, potentially leading to full system compromise. All users running vulnerable versions of Microsoft Office are affected.
💻 Affected Systems
- Microsoft Office
- Microsoft 365 Apps
📦 What is this software?
365 Apps by Microsoft
365 Apps by Microsoft
Office by Microsoft
Office by Microsoft
Office by Microsoft
Office 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 →
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 →
Office Long Term Servicing Channel by Microsoft
View all CVEs affecting Office Long Term Servicing Channel →
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover with administrative privileges, data theft, ransomware deployment, and persistent backdoor installation.
Likely Case
Local privilege escalation leading to unauthorized access to sensitive files, credential harvesting, and lateral movement within the network.
If Mitigated
Limited impact with application sandboxing and proper user privilege restrictions, potentially only causing application crashes.
🎯 Exploit Status
Requires user interaction to open malicious document. No public exploit code available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: To be determined from Microsoft Security Update
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-54906
Restart Required: Yes
Instructions:
1. Open any Office application. 2. Go to File > Account > Update Options > Update Now. 3. Restart Office applications after update completes. 4. For enterprise deployments, deploy through Microsoft Endpoint Configuration Manager or equivalent.
🔧 Temporary Workarounds
Disable Office macro execution
windowsPrevents execution of malicious macros in Office documents
Set GPO: Computer Configuration > Administrative Templates > Microsoft Office 2016 > Security Settings > Trust Center > Disable all macros without notification
Enable Protected View
windowsOpens documents from untrusted sources in read-only mode
Set GPO: User Configuration > Administrative Templates > Microsoft Office 2016 > Security Settings > Trust Center > Protected View > Enable Protected View for files originating from the Internet
🧯 If You Can't Patch
- Implement application whitelisting to block unauthorized Office document execution
- Deploy endpoint detection and response (EDR) solutions with behavior-based detection for Office process anomalies
🔍 How to Verify
Check if Vulnerable:
Check Office version against patched versions in Microsoft Security AdvisoryCheck Version:
In Word/Excel: File > Account > About [Application] shows version numberVerify Fix Applied:
Verify Office build number matches or exceeds patched version from Microsoft advisory📡 Detection & Monitoring
Log Indicators:
- Office application crashes with memory access violations
- Unusual child processes spawned from Office applications
- Suspicious PowerShell or cmd.exe execution from Office processes
Network Indicators:
- Office applications making unexpected outbound connections
- DNS queries to suspicious domains following document opening
SIEM Query:
source="windows-security" EventID=4688 AND NewProcessName="powershell.exe" AND ParentProcessName="WINWORD.EXE"