CVE-2025-24075
📋 TL;DR
A stack-based buffer overflow vulnerability in Microsoft Office Excel allows attackers to execute arbitrary code on vulnerable systems by tricking users into opening malicious Excel files. This affects all users running unpatched versions of Microsoft Excel. Successful exploitation requires user interaction to open a specially crafted Excel document.
💻 Affected Systems
- Microsoft Excel
📦 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
Complete system compromise with attacker gaining full control of the victim's computer, enabling data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local code execution with the privileges of the current user, potentially leading to data exfiltration, credential harvesting, or installation of persistent malware.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially resulting in application crash rather than code execution.
🎯 Exploit Status
Exploitation requires social engineering to deliver malicious Excel file and user interaction to open it. No known public exploits at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: To be determined from Microsoft's security update
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-24075
Restart Required: No
Instructions:
1. Open Excel and go to File > Account > Update Options > Update Now. 2. Install all available Office updates. 3. Alternatively, use Windows Update to install the latest Office security patches.
🔧 Temporary Workarounds
Disable automatic Excel file opening
allPrevent Excel from automatically opening files from untrusted sources
Enable Protected View
allForce all Excel files from internet sources to open in Protected View
🧯 If You Can't Patch
- Restrict Excel file execution via application control policies
- Implement email filtering to block suspicious Excel attachments
🔍 How to Verify
Check if Vulnerable:
Check Excel version against Microsoft's security advisory for affected versionsCheck Version:
In Excel: File > Account > About ExcelVerify Fix Applied:
Verify Excel has been updated to the patched version specified in Microsoft's advisory📡 Detection & Monitoring
Log Indicators:
- Excel process crashes with unusual error codes
- Suspicious child processes spawned from Excel
Network Indicators:
- Outbound connections from Excel process to unknown IPs
- DNS requests for suspicious domains after Excel file opening
SIEM Query:
Process Creation where Parent Process contains 'excel.exe' AND Command Line contains unusual parameters