CVE-2024-30073: Windows Security Zone Mapping Security Feature Bypass Vulnerability Explained with Code Snippet and Exploit Details

Microsoft Windows Security Zones offer a mechanism for organizing content, such as web pages and ActiveX controls, based on their trustworthiness. As a user, this helps you to control what actions are allowed for each of these content items. A recently discovered vulnerability known as CVE-2024-30073 allows attackers to bypass the Security Zone Mapping feature in some scenarios.

In this post, we will explore how this vulnerability may be exploited, potential mitigating solutions, and ways to ensure your systems remain secure. We'll also take a look at a code snippet to better understand the vulnerability and offer links to original references related to the subject.

Root Cause Analysis

The vulnerability present in the Security Zone Mapping feature of Microsoft Windows stems from the incorrect handling of certain outcomes when the "Local intranet" or "Trusted sites" zones are utilized. An attacker can exploit this flaw to bypass security checks, ultimately allowing potentially higher access permissions.

The technical details of this issue can be found in the National Vulnerability Database (NVD) entry

CVE-2024-30073 - NVD

Exploit

The exploit would rely on an attacker's ability to manipulate the target system's environment to abuse the local intranet or trusted sites security zones. This may include setting unexpected domain mappings or tweaking the browser settings.

For instance, the attacker crafts a malicious HTML page, embed it as an iframe, and leverage either the local intranet or trusted sites security zones to manipulate the parent frame containing the victim's data/content.

Here's some sample code to better understand the attack scenario

<!DOCTYPE html>
<html>
<head>
    <title>Example - CVE-2024-30073</title>
</head>
<body>
    <h1>Victim's Content</h1>
    
    <iframe src="malicious.html" seamless></iframe>
</body>
</html>

malicious.html file

<!DOCTYPE html>
<html>
<head>
    <title>Attacker's Page (Malicious)</title>
    <script>
        window.onload = function() {
            // Exploit code to access parent frame window and fetch content
            const parentContent = window.parent.document.body.innerHTML;
            alert("Victims content grabbed: " + parentContent);
            // Further malicious actions
        };
    </script>
</head>
<body>
    Attacker's malicious content
</body>
</html>

Mitigation

To mitigate this vulnerability, Microsoft has released a security update addressing the issue. Applying this patch will fix the issue and ensure that users are adequately protected. Check out the Microsoft Security Update Guide for more information on the relevant update:
Microsoft Security Update Guide - CVE-2024-30073

In addition to applying the security update, users are advised to continuously update their software and apply the latest security patches. Administrators should follow the principles of least privilege, limiting access and permissions to only what is required.

Conclusion

CVE-2024-30073, a Windows Security Zone Mapping Security Feature Bypass Vulnerability, provides an opportunity for attackers to exploit the incorrect handling of the local intranet or trusted sites security zones. By understanding how this vulnerability might be exploited and staying vigilant about system updates, you can help to ensure that your systems remain secure.

Timeline

Published on: 09/10/2024 17:15:16 UTC
Last modified on: 10/09/2024 01:26:42 UTC