The CVE-2023-4077 vulnerability is found in Google Chrome's extension system and has the potential to allow an attacker to inject scripts or HTML into privileged pages if they can convince a user to install a malicious extension. This vulnerability exists in Google Chrome versions prior to 115..579.170. In this post, we will explore the details of the vulnerability, provide code snippets for proof-of-concept, and offer potential exploit details. We will also provide links to original references for a comprehensive understanding of the issue.

CVE-2023-4077 Explained

CVE-2023-4077 revolves around insufficient data validation in Google Chrome's extension system. Chrome extensions, built using web technologies like HTML, JavaScript, and CSS, enhance the browser's functionality and user experience. Unfortunately, this extension system comes with some risks.

In this vulnerability, an attacker could inject malicious scripts or HTML into a privileged page. This is possible because the extension system does not adequately validate some data that extensions operate on. This issue is classified by Chromium as a security severity with a medium level.

- Chromium Security Bulletin

Proof-of-Concept

The following proof-of-concept demonstrates a simple malicious Chrome extension that attempts to exploit the CVE-2023-4077 vulnerability. This code snippet shows how the extension could inject a script into a privileged page:

// background.js
chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
  if (changeInfo.status === 'complete' && tab.url.startsWith('chrome://')) {
    // Inject malicious script into the privileged page
    chrome.tabs.executeScript(
      tabId,
      {
        code: `
          // Malicious code to be executed
          console.log("Malicious code executed");`;
      },
      function() {
        if (chrome.runtime.lastError) {
          console.error(chrome.runtime.lastError);
        }
      }
    );
  }
});

// manifest.json
{
  "manifest_version": 2,
  "name": "Malicious Extension",
  "version": "1.",
  "permissions": ["tabs"],
  "background": {
    "scripts": ["background.js"]
  }
}

Potential Exploit Details

Here are some possible techniques an attacker could use to take advantage of the CVE-2023-4077 vulnerability:

1. Social Engineering: An attacker might use social engineering techniques to convince a user to install their malicious extension, misleading them into believing the extension carries a benign purpose.

2. Man-in-the-Middle Attack: An attacker may intercept an extension's communication with the privileged page in order to inject their malicious scripts.

3. Suspicious Download: An attacker can create a malicious extension and have it listed alongside more legitimate extensions, hoping to capitalize on an unsuspecting user downloading their extension inadvertently.

Mitigation

To mitigate the CVE-2023-4077 vulnerability, users should update their Google Chrome browser to version 115..579.170 or later. This update addresses the insufficient data validation issue and protects users from potential attacks exploiting this vulnerability.

Conclusion

CVE-2023-4077 poses a significant risk to users running Google Chrome with outdated versions, as attackers could exploit the vulnerability to inject scripts or HTML into privileged pages. Prevention is as simple as ensuring the browser is updated and running the latest version. We hope this information helps in understanding the risks associated with this vulnerability and the importance of keeping software updated for security purposes.

Timeline

Published on: 08/03/2023 01:15:00 UTC
Last modified on: 08/12/2023 06:21:00 UTC