CVE-2025-29815
📋 TL;DR
A use-after-free vulnerability in Microsoft Edge (Chromium-based) allows an authenticated attacker to execute arbitrary code remotely over a network. This affects users running vulnerable versions of Microsoft Edge on any supported operating system. The attacker must have some level of access to the target system or network.
💻 Affected Systems
- Microsoft Edge (Chromium-based)
📦 What is this software?
Edge Chromium by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with remote code execution leading to data theft, ransomware deployment, or lateral movement across the network.
Likely Case
Limited code execution in the context of the Edge browser process, potentially leading to session hijacking, credential theft, or installation of malware.
If Mitigated
Browser sandboxing may limit impact to the browser process, but attackers could still steal sensitive data or use the foothold for further attacks.
🎯 Exploit Status
Exploitation requires the attacker to be authenticated on the target system or network. The use-after-free vulnerability requires specific memory manipulation techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Microsoft Edge version 125.0.2535.51 or later
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-29815
Restart Required: Yes
Instructions:
1. Open Microsoft Edge. 2. Click the three-dot menu in the top right. 3. Go to Help and Feedback > About Microsoft Edge. 4. The browser will automatically check for and install updates. 5. Restart the browser when prompted.
🔧 Temporary Workarounds
Disable Edge browser usage
allTemporarily restrict or block Microsoft Edge usage until patching can be completed.
Enable Enhanced Security Mode
allConfigure Edge's Enhanced Security Mode to provide additional protection against memory corruption attacks.
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable systems
- Deploy application whitelisting to prevent unauthorized code execution
🔍 How to Verify
Check if Vulnerable:
Check Edge version by navigating to edge://settings/help. If version is below 125.0.2535.51, the system is vulnerable.Check Version:
On Windows: """C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --version"""Verify Fix Applied:
After updating, verify the Edge version is 125.0.2535.51 or higher in edge://settings/help.📡 Detection & Monitoring
Log Indicators:
- Unusual Edge process behavior
- Memory access violations in Edge logs
- Suspicious child processes spawned from Edge
Network Indicators:
- Unusual outbound connections from Edge processes
- Traffic patterns suggesting command and control
SIEM Query:
Process Creation where (Image contains "msedge.exe") AND (CommandLine contains suspicious patterns)