Google Chrome has always been a popular choice for browsing the web, mainly due to its speed, simplicity, and security features. However, even the most secure of systems can have vulnerabilities, and Google Chrome is no exception. In this post, I will discuss a low severity security issue in Google Chrome (CVE-2023-1233) that can be exploited to gain potentially sensitive information from the API via a maliciously-crafted Chrome Extension.

Before we dive deep into the details, let's briefly explain what CVEs are. CVEs or Common Vulnerabilities and Exposures are a list of publicly disclosed security vulnerabilities affecting software. This identification system allows developers and security professionals to communicate effectively about specific security flaws or areas they have discovered in IT systems. In our case, the CVE code is CVE-2023-1233, affecting the Resource Timing feature in Google Chrome versions prior to 111..5563.64.

Exploit Details

The vulnerability revolves around insufficient policy enforcement in Resource Timing. Resource Timing is a feature that provides developers with detailed information about the loading time of various resources (such as images, scripts, etc.) on a webpage. This data is vital in optimizing a website's performance.

However, in Google Chrome versions before 111..5563.64, an attacker could exploit this feature to gain potentially sensitive information from the API through a malicious Chrome Extension. To do this, the threat actor would need to convince the victim/user to install the malicious extension.

Here's an example of a code snippet an attacker might use in a malicious Chrome extension

// Code to request access to Resource Timing data
chrome.permissions.request({permissions: ['resourceTiming']}, function(granted) {
  if (granted) {
    // If access is granted, fetch Resource Timing data
    var resourceTimingData = window.performance.getEntriesByType('resource');

    // Process the data and potentially leak sensitive information
    resourceTimingData.forEach(function(resource) {
      console.log('Resource:',, 'Duration:', resource.duration);

The code above requests permission to access Resource Timing data and, once granted, logs the sensitive information to the console. In a real-world scenario, the attacker would likely send this information to their server to use as they please, rather than logging it to the console.

Fixes and Mitigation

Google has addressed this issue in Chrome version 111..5563.64. Users are advised to ensure they have updated their Google Chrome to the latest version to protect themselves from this vulnerability. The simplest way to do this is by navigating to "chrome://settings/help" or by clicking on the three-dot menu on the top right corner, selecting "Help," and choosing "About Google Chrome."

Original References

1. Chromium Issue Tracker - The original bug report detailing the vulnerability in Chromium's issue tracker.
2. CVE Entry for CVE-2023-1233 - The official CVE entry for this vulnerability.
3. Google Chrome Releases Blog - Announcement of the stable channel update, which includes the fix for this issue.


Although CVE-2023-1233 is categorized as a low-severity vulnerability, it is still crucial for users to keep their software updated to minimize the risks. Regularly updating Google Chrome should keep you protected against this and other vulnerabilities that may arise in the future. Keeping a watchful eye on the permissions you grant to Chrome Extensions is also an essential aspect of maintaining secure browsing habits.


Published on: 03/07/2023 22:15:00 UTC
Last modified on: 03/10/2023 20:24:00 UTC