CVE-2025-48812
📋 TL;DR
This vulnerability allows an attacker to read memory outside the intended buffer in Microsoft Excel, potentially exposing sensitive information from the application's memory. It affects users who open malicious Excel files with vulnerable versions of Microsoft Office.
💻 Affected Systems
- Microsoft Excel
- Microsoft Office
📦 What is this software?
365 Apps by Microsoft
365 Apps by Microsoft
Excel by Microsoft
Excel 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
An attacker could extract sensitive data like passwords, encryption keys, or document contents from Excel's memory, leading to data breach or credential theft.
Likely Case
Limited information disclosure from Excel's process memory, potentially revealing fragments of other documents or system information.
If Mitigated
With proper security controls, the impact is minimal as it requires user interaction and only discloses local memory contents.
🎯 Exploit Status
Requires user to open a specially crafted Excel file. No public exploit code available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific version
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-48812
Restart Required: Yes
Instructions:
1. Open Microsoft Excel
2. Go to File > Account > Update Options
3. Select 'Update Now'
4. Restart Excel when prompted
5. Alternatively, install latest Office updates via Windows Update
🔧 Temporary Workarounds
Disable Excel file opening
windowsPrevent Excel from opening files from untrusted sources
Use Protected View
windowsEnsure Protected View is enabled for files from internet
🧯 If You Can't Patch
- Restrict Excel file execution via application control policies
- Educate users to avoid opening Excel files from untrusted sources
🔍 How to Verify
Check if Vulnerable:
Check Excel version against patched versions in Microsoft advisoryCheck Version:
In Excel: File > Account > About ExcelVerify Fix Applied:
Verify Excel version is updated to patched version and test with known safe files📡 Detection & Monitoring
Log Indicators:
- Excel crash logs with memory access violations
- Unexpected Excel process termination
Network Indicators:
- None - local exploitation only
SIEM Query:
EventID=1000 OR EventID=1001 with Excel.exe in Application logs