CVE-2025-49713: Microsoft Edge Chromium RCE Vulnerability

CVE-2025-49713 Overview

CVE-2025-49713 is a type confusion vulnerability (CWE-843) in Microsoft Edge (Chromium-based) that allows an unauthorized attacker to execute arbitrary code over a network. This vulnerability stems from improper handling of resource types, where the browser engine accesses a resource using an incompatible type, potentially leading to memory corruption and code execution.

Critical Impact

Successful exploitation of this type confusion vulnerability could allow remote attackers to execute arbitrary code on vulnerable systems, potentially leading to complete system compromise with access to sensitive data and the ability to install malware.

Affected Products

• Microsoft Edge (Chromium-based)

Discovery Timeline

• 2025-07-02 - CVE-2025-49713 published to NVD
• 2025-07-08 - Last updated in NVD database

Technical Details for CVE-2025-49713

Vulnerability Analysis

This vulnerability is classified as a type confusion issue (CWE-843), which occurs when a program accesses a resource using an incompatible type. In the context of Microsoft Edge's Chromium-based rendering engine, type confusion vulnerabilities typically arise in the JavaScript engine or DOM handling code when objects are misinterpreted as different types than they actually are.

The network-based attack vector means an attacker can trigger this vulnerability remotely, typically through malicious web content. User interaction is required for exploitation, meaning a victim must visit a crafted webpage or interact with malicious content for the attack to succeed.

Root Cause

The root cause of this vulnerability lies in improper type validation within Microsoft Edge's Chromium-based code. When processing certain resources or objects, the browser fails to properly verify or enforce type consistency, allowing an attacker to craft input that causes the browser to treat an object as a different type. This type mismatch can lead to out-of-bounds memory access or corruption of critical data structures.

Attack Vector

The attack vector for CVE-2025-49713 is network-based, requiring user interaction. An attacker could exploit this vulnerability by:

1. Crafting a malicious webpage containing specially designed JavaScript or HTML content
2. Luring a victim to visit the malicious page through phishing, malvertising, or compromised legitimate websites
3. When the victim visits the page, the malicious content triggers the type confusion condition in the browser's rendering engine
4. Successful exploitation could allow the attacker to execute arbitrary code in the context of the current user

The vulnerability does not require any privileges on the target system, making it accessible to any attacker who can deliver malicious web content to potential victims.

Detection Methods for CVE-2025-49713

Indicators of Compromise

• Unusual browser process crashes or memory access violations in Microsoft Edge
• Suspicious network connections originating from msedge.exe to unknown or malicious domains
• Evidence of unexpected child processes spawned by the Edge browser process
• Anomalous memory allocation patterns in browser telemetry logs

Detection Strategies

• Deploy endpoint detection and response (EDR) solutions to monitor for exploitation attempts targeting browser processes
• Enable browser crash reporting and analyze crash dumps for signs of memory corruption
• Implement network monitoring to detect connections to known malicious infrastructure
• Use behavioral analysis to identify abnormal browser process activity such as unexpected code execution

Monitoring Recommendations

• Monitor Microsoft Edge process behavior for signs of exploitation including unusual memory operations
• Review application event logs for Edge-related errors or crashes
• Implement web filtering to block access to known malicious domains that may host exploit code
• Enable enhanced security features in Microsoft Defender for Endpoint to detect browser-based attacks

How to Mitigate CVE-2025-49713

Immediate Actions Required

• Update Microsoft Edge to the latest patched version immediately
• Enable automatic updates for Microsoft Edge to ensure timely deployment of security patches
• Consider temporarily restricting access to untrusted websites until patching is complete
• Review and enable browser security features such as SmartScreen and Enhanced Security Mode

Patch Information

Microsoft has released a security update to address this vulnerability. Administrators and users should apply the update as soon as possible. For detailed patch information and installation instructions, refer to the Microsoft Security Update Guide.

To update Microsoft Edge:

1. Open Microsoft Edge and navigate to edge://settings/help
2. Edge will automatically check for and install available updates
3. Restart the browser after the update completes

Workarounds

• Enable Microsoft Edge's Enhanced Security Mode which provides additional protections against exploitation
• Use web content filtering to block access to potentially malicious websites
• Consider disabling JavaScript on untrusted sites using browser extensions or enterprise policies
• Implement network-level protections such as web proxies with threat intelligence feeds

# Verify Microsoft Edge version via command line
# Windows PowerShell - Check installed Edge version
(Get-Item "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe").VersionInfo.ProductVersion

# Enable automatic updates via Group Policy (for enterprise environments)
# Navigate to: Computer Configuration > Administrative Templates > Microsoft Edge Update > Applications > Microsoft Edge
# Set "Update policy override" to "Always allow updates"