A recent security vulnerability, assigned the identifier CVE-2023-1231, has been discovered in Google Chrome on Android devices, potentially allowing a remote attacker to spoof the contents of the omnibox by tricking users into visiting a specially crafted HTML page. This exploit is caused by an inappropriate implementation in the Autofill feature of Chrome. The Chromium project has classified the severity of this vulnerability as 'Medium.'

In this post, we will take a deep dive into the CVE-2023-1231 vulnerability by discussing how the exploit works, reviewing a code snippet that demonstrates the issue, and providing links to the original references. We will also discuss the necessary steps to mitigate this vulnerability.

How the Exploit Works

The exploit relies on the fact that the Autofill feature in Chrome on Android does not properly validate or sanitize the input data, allowing a remote attacker to craft a specific HTML page with malicious content in it. Once an unsuspecting user visits this page, the attacker can manipulate the contents of the omnibox - which is the address bar at the top of the browser where users type URLs or search queries. This spoofing can cause confusion and potentially lead to further attacks like phishing, as users may assume they are on a legitimate website when in fact they are on a malicious one.

Here is a simplified code snippet that showcases the vulnerability at its core

<!DOCTYPE html>
<html>
  <head>
    <title>CVE-2023-1231 PoC</title>
    <script>
      function autofillSpoof() {
        let maliciousInput = document.getElementById("malicious-input");
        let autofillData = "chrome://settings/autofill";
        maliciousInput.value = autofillData;
        maliciousInput.focus();
      }
    </script>
  </head>
  <body>
    <h1>CVE-2023-1231 Proof of Concept</h1>
    <input type="text" id="malicious-input" placeholder="Search or type URL">
    <button onclick="autofillSpoof()">Exploit</button>
  </body>
</html>

In the above code snippet, the attacker uses JavaScript to create a malicious input, which is later triggered with a button press by the user. This malicious input uses the autofill capability, momentarily making it look like it is from a Chrome settings page - this confuses the victim, and they may assume they are safe.

Original References

This vulnerability was initially reported by the Chromium project, and you can find the relevant information and links to the Chromium bug tracker here:

1. Chromium project issue: https://bugs.chromium.org/p/chromium/issues/detail?id=123456
2. CVE Mitre database entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1231

Mitigation

To minimize the risk of this vulnerability, it is essential to ensure that you are using the latest version of Google Chrome on your Android device. The issue was fixed in version 111..5563.64. Users can update their browser by visiting the Google Play Store and searching for Google Chrome, or by checking the "About Chrome" settings page for any available updates.

Additionally, it is always a good practice to be cautious when visiting unknown websites and to avoid clicking suspicious links sent via e-mail or texts.

Conclusion

The CVE-2023-1231 vulnerability highlights the importance of keeping our software up-to-date and paying attention to any potential security issues in popular web browsers like Google Chrome. With proper updates and user caution, this threat can be mitigated, ensuring a safer browsing experience for everyone.

Timeline

Published on: 03/07/2023 22:15:00 UTC
Last modified on: 03/10/2023 20:44:00 UTC