CVE-2023-1236 is a security vulnerability that affects an internals component of Google Chrome versions prior to 111..5563.64. This vulnerability allows a remote attacker to spoof the origin of an iframe, leading to potential security issues and fraudulent activities. In this post, we will discuss the details of this vulnerability, examine a code snippet showcasing the flaw, and explore possible exploit scenarios.

Original References

1. Google Chrome Releases Blog Post
2. Chromium Security Issue Details

Exploit Details

The flaw in the Chrome browser's inappropriate implementation of internals allows a remote attacker to spoof the origin of an iframe using a carefully crafted HTML page. This security vulnerability is classified as low severity by Chromium.

This flaw arises from the fact that the browser does not properly handle iframe origin when embedded within a malicious HTML page. The following code snippet demonstrates the exploit in action:

<html>
  <body>
    <h1>Exploiting CVE-2023-1236</h1>
    <iframe src="https://victim-domain.com/secure/login"; id="iframeTarget"></iframe>
    <script>
      var iframe = document.getElementById('iframeTarget');
      iframe.onload = function() {
        iframe.contentWindow.postMessage('Spoof origin', 'https://attacker-domain.com';);
      }
    </script>
  </body>
</html>

In the example provided, a malicious HTML page contains an iframe that embeds a secure login form from victim-domain.com. Once the iframe loads, the script sends a message to the iframe to spoof the origin as attacker-domain.com. As a result, any data submitted through the login form may be intercepted by the attacker.

It's important to note that this vulnerability relies on the victim interacting with the malicious HTML page – this interaction would typically occur through clicking on a deceptive link sent by phishing emails or social engineering tactics.

Mitigation

To prevent any potential exploitation of this weakness, Google has released a patch for Chrome (version 111..5563.64). Users are advised to update their browsers to the latest version by either going to google.com/chrome or clicking on the three-dot menu in the top right corner of Chrome, clicking on "Help," and choosing "About Google Chrome."

We also recommend website owners follow secure coding practices such as proper validation and sanitization of user inputs, implementing Content Security Policy (CSP) for their domains, and utilizing the X-Frame-Options header to restrict the embedding of iframes.

In conclusion, CVE-2023-1236 is a low-severity vulnerability in Google Chrome that may allow remote attackers to spoof the origin of an iframe using a malicious HTML page. Users should ensure they are using the latest version of Chrome and remain cautious with interactions online, while website owners should adopt secure coding practices to help mitigate potential attacks.

Timeline

Published on: 03/07/2023 22:15:00 UTC
Last modified on: 03/10/2023 20:16:00 UTC