CVE-2025-29795
📋 TL;DR
This vulnerability in Microsoft Edge allows an authorized attacker to exploit improper link resolution to elevate privileges locally. It affects users running vulnerable versions of Microsoft Edge on Windows systems. Attackers could gain higher privileges than intended by manipulating symbolic links or junctions.
💻 Affected Systems
- Microsoft Edge (Chromium-based)
📦 What is this software?
Edge Update by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An authenticated attacker could achieve full system compromise by elevating to SYSTEM or administrator privileges, potentially installing malware, stealing sensitive data, or persisting on the system.
Likely Case
An attacker with initial access could elevate privileges to bypass security controls, access restricted files, or install additional malicious software.
If Mitigated
With proper user account controls and least privilege principles, impact would be limited to the user's own context rather than full system compromise.
🎯 Exploit Status
Exploitation requires the attacker to have some level of access to the system and knowledge of link following techniques. The CWE-59 (Improper Link Resolution Before File Access) suggests manipulation of symbolic links or junctions.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Edge version in Settings > About Microsoft Edge for the latest patched version
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-29795
Restart Required: No
Instructions:
1. Open Microsoft Edge
2. Click the three-dot menu in top-right
3. Go to Settings > About Microsoft Edge
4. Allow Edge to check for and install updates automatically
5. Restart Edge if prompted
🔧 Temporary Workarounds
Disable Edge via Group Policy
WindowsTemporarily disable Microsoft Edge usage while awaiting patch deployment
gpedit.msc > Computer Configuration > Administrative Templates > Windows Components > Microsoft Edge > 'Allow Microsoft Edge to start and load the Start and New Tab page at Windows startup and each time Microsoft Edge is closed' = Disabled
🧯 If You Can't Patch
- Implement strict least privilege principles - ensure users run with minimal necessary permissions
- Monitor for suspicious file access patterns and privilege escalation attempts using endpoint detection tools
🔍 How to Verify
Check if Vulnerable:
Check Microsoft Edge version in Settings > About Microsoft Edge and compare against Microsoft's security advisory for patched versionsCheck Version:
edge://settings/help or check 'About Microsoft Edge' in settingsVerify Fix Applied:
Verify Edge version is updated to the patched version in Settings > About Microsoft Edge📡 Detection & Monitoring
Log Indicators:
- Windows Security Event Logs showing unexpected privilege escalation
- Edge process spawning with elevated privileges
- Suspicious file access patterns involving symbolic links
Network Indicators:
- Not applicable - this is a local privilege escalation vulnerability
SIEM Query:
EventID=4688 AND ProcessName="msedge.exe" AND NewProcessId!="*" AND SubjectUserName!="SYSTEM" AND TokenElevationType="%%1936"