CVE-2025-21404
📋 TL;DR
This vulnerability in Microsoft Edge allows attackers to spoof UI elements, potentially tricking users into interacting with malicious content. It affects users of Microsoft Edge (Chromium-based) on supported Windows systems. The vulnerability requires user interaction to be exploited.
💻 Affected Systems
- Microsoft Edge (Chromium-based)
📦 What is this software?
Edge Chromium by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An attacker could create convincing fake UI elements that trick users into revealing sensitive information, downloading malware, or performing unintended actions.
Likely Case
Phishing attacks where users are tricked into clicking on malicious links or entering credentials into spoofed interfaces.
If Mitigated
Limited impact with proper user awareness training and security controls in place.
🎯 Exploit Status
Exploitation requires user interaction (visiting a malicious website). No authentication is required to trigger the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Microsoft Edge version 124.0.2478.51 or later
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21404
Restart Required: Yes
Instructions:
1. Open Microsoft Edge. 2. Click Settings (three dots) > Help and feedback > About Microsoft Edge. 3. Browser will automatically check for updates and install if available. 4. Restart Edge when prompted.
🔧 Temporary Workarounds
Disable JavaScript
allPrevents execution of malicious scripts that could exploit the spoofing vulnerability.
Use Enhanced Security Mode
windowsEnable Microsoft Edge's Enhanced Security Mode for additional protection against web-based threats.
🧯 If You Can't Patch
- Implement web filtering to block known malicious websites
- Deploy user awareness training about phishing and suspicious websites
🔍 How to Verify
Check if Vulnerable:
Check Microsoft Edge version: Open Edge > Settings > About Microsoft Edge. If version is below 124.0.2478.51, system is vulnerable.Check Version:
msedge --versionVerify Fix Applied:
Verify Microsoft Edge version is 124.0.2478.51 or higher after applying updates.📡 Detection & Monitoring
Log Indicators:
- Unusual browser extension activity
- Multiple failed authentication attempts from browser sessions
Network Indicators:
- Connections to known malicious domains from Edge browser
SIEM Query:
source="Microsoft-Windows-Security-Auditing" EventCode=4688 | where ProcessName contains "msedge.exe"