CVE-2025-29822
📋 TL;DR
This vulnerability allows an unauthorized attacker to bypass a security feature in Microsoft Office OneNote by exploiting an incomplete list of disallowed inputs. Attackers could potentially execute malicious code or access restricted functionality locally. Users of affected Microsoft Office OneNote versions are at risk.
💻 Affected Systems
- Microsoft Office OneNote
📦 What is this software?
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 →
Office Long Term Servicing Channel by Microsoft
View all CVEs affecting Office Long Term Servicing Channel →
Onenote by Microsoft
Onenote by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation leading to complete system compromise through arbitrary code execution.
Likely Case
Bypass of security controls allowing unauthorized access to protected OneNote features or data.
If Mitigated
Limited impact with proper application control policies and restricted user privileges.
🎯 Exploit Status
Requires local access and knowledge of the incomplete input validation. No public exploit code available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Will be specified in Microsoft's monthly security updates
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-29822
Restart Required: Yes
Instructions:
1. Open Microsoft Office application
2. Go to File > Account > Update Options
3. Select 'Update Now'
4. Restart computer when prompted
5. Verify update through Windows Update history
🔧 Temporary Workarounds
Restrict OneNote Execution
windowsUse application control policies to restrict OneNote execution to trusted locations only
Using AppLocker or Windows Defender Application Control policies
Disable Local Script Execution
windowsConfigure OneNote to disable local script execution features
Set registry key: HKCU\Software\Microsoft\Office\16.0\OneNote\Options\Other\DisableLocalScriptExecution = 1
🧯 If You Can't Patch
- Implement least privilege principles - restrict user accounts to standard user privileges
- Use application whitelisting to prevent unauthorized OneNote modifications or script execution
🔍 How to Verify
Check if Vulnerable:
Check Office version against Microsoft's security bulletin for affected versionsCheck Version:
In OneNote: File > Account > About OneNoteVerify Fix Applied:
Verify Office version is updated to the patched version specified in Microsoft's security update📡 Detection & Monitoring
Log Indicators:
- Unusual OneNote process behavior
- Attempts to access restricted OneNote features
- Security feature bypass attempts in application logs
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
EventID=4688 AND ProcessName='onenote.exe' AND CommandLine CONTAINS suspicious_pattern