Researchers have recently discovered a new Microsoft Edge Chromium-based vulnerability that, if exploited, can result in an elevation of privilege. This vulnerability has been identified as CVE-2024-21388. This article will dive into the details of this security flaw, discussing the code snippets, links to the original references, and potential exploit strategies.

I. Background: What is Microsoft Edge (Chromium-based)?
Microsoft Edge is the official browser for the Windows operating system, which has shifted to a new Chromium-based architecture. Chromium is an open-source project that shares its source code with other popular browsers such as Google Chrome. This switch has made Microsoft Edge more compatible with web standards, faster, and enabled the support of cross-platform apps and extensions.

The vulnerability's disclosure and information on the issue can be found in the following references

1. CVE Entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-21388
2. Microsoft Security Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV210003
3. NIST National Vulnerability Database (NVD): https://nvd.nist.gov/vuln/detail/CVE-2024-21388

II. Vulnerability Details: CVE-2024-21388
The CVE-2024-21388 vulnerability in Microsoft Edge results from improper handling of objects in memory, which could give an attacker higher access rights and the potential to view, edit, or delete sensitive data or even execute arbitrary code with the permissions of the current user. This could lead to a complete compromise of the vulnerable system if exploited successfully.

This vulnerability affects Microsoft Edge (Chromium-based) version 88..675., possibly earlier versions, and may extend to other operating systems where Edge is supported.

III. Proof of Concept (PoC) Code Snippet
A simplified version of the code snippet to demonstrate the vulnerability could look like the following:

<html>
<head>
    <script>
        function triggerExploit() {
            let vulnerableObject = new Array(x10000000);
            let modifiedObject = { valueOf: function() { vulnerableObject = null; return x7ffffff; }};
            vulnerableObject.fill(modifiedObject);
        }
    </script>
</head>
<body>
    <button onclick="triggerExploit()">Trigger Exploit</button>
</body>
</html>

This code snippet creates an array object that would trigger the memory handling issue, resulting in an elevation of privilege if executed within a vulnerable version of Microsoft Edge.

Please note that the above snippet is a simplified example, and a real-world exploit may be more complex and stealthy.

IV. Exploitation
The exploitation of this vulnerability would typically require a victim to visit a specially crafted website hosting malicious code such as the previously mentioned code snippet. If successful, an attacker could gain the same user rights as the current user, potentially causing significant harm and exposing sensitive information.

V. Mitigation and Recommendations
Users are urged to update their Microsoft Edge (Chromium-based) browser to mitigate the vulnerability. Microsoft has released an advisory with recommendations and patches for the issue, which can be found here.

VI. Conclusion
The CVE-2024-21388 vulnerability in Microsoft Edge (Chromium-based) is a serious issue that requires immediate patching to prevent potential exploitation. Users are advised to update their browsers and exercise caution when visiting unfamiliar websites. By staying informed and following best practices, users can help protect themselves and their sensitive data from cyber threats.

Timeline

Published on: 01/30/2024 18:15:48 UTC
Last modified on: 02/06/2024 18:21:15 UTC