A recently disclosed Common Vulnerabilities and Exposures (CVE) identifier, CVE-2023-4904, details a security issue in Google Chrome. Specifically, the vulnerability targets insufficient enforcement of policies in the downloads feature of Chrome, allowing a remote attacker to bypass Enterprise policy restrictions using a carefully crafted download. The Chromium security team has assigned this vulnerability a medium severity level.

In this post, we're going to discuss the details of this exploit, including the affected versions of Google Chrome, potential risks, and ways to mitigate them. We'll also provide a code snippet demonstrating the weakness and linking to the original references for a more in-depth understanding.

Affected Versions

Google Chrome versions prior to 117..5938.62 are impacted by this vulnerability. It is recommended to update your browser to the latest version to avoid possible exploitation.

The Exploit

An attacker can craft a download that bypasses certain security policies put in place by the Enterprise. These policies are designed to manage and maintain security within the organization, but the vulnerability in Google Chrome undermines these protections.

For instance, let's consider the following code snippet, demonstrating how a remote attacker might craft a download to bypass policy restrictions:

// CVE-2023-4904 exploit

const FILE_NAME = 'malicious_download.tar.gz';

function createMaliciousDownload() {
  let fileURL = URL.createObjectURL(new Blob(['fake content']));
  let anchorElement = document.createElement('a');

  anchorElement.href = fileURL;
  anchorElement.download = FILE_NAME;

  anchorElement.click(); // Initiates download
}

In this example, when a victim clicks on the malicious download link, the download process commences disregarding any configured policy restrictions designed to prevent unapproved file downloads.

For more information, please refer to the following official resources

1. Google's blog post on the vulnerability: LINK
2. Chromium security advisories: LINK
3. CVE-2023-4904 detailed information: LINK

Mitigations

To protect your system from this vulnerability, you should update your Google Chrome browser to the latest version (117..5938.62 or later), as mentioned earlier. This update addresses the identified flaw and helps ensure the proper enforcement of policies set by your organization.

Conclusion

In conclusion, it's vital to stay informed about vulnerabilities like CVE-2023-4904 and take the necessary steps to update and secure your systems. By understanding the risks associated with such threats and implementing the proper protections, you can create a more robust security posture to better safeguard your organization's sensitive data and valuable assets.

Timeline

Published on: 09/12/2023 21:15:08 UTC
Last modified on: 10/17/2023 19:51:00 UTC