CVE-2023-0134 - Use-After-Free Vulnerability in Google Chrome's Cart Prior to Version 109..5414.74: Exploit Details and Remediation

In this long read post, we will be discussing the CVE-2023-0134 - a medium-severity security vulnerability affecting Google Chrome prior to version 109..5414.74. Specifically, we will look into the use-after-free vulnerability present in Chrome's Cart and how it can lead to potential heap corruption via database corruption and a crafted HTML page. We will also share the code snippets relating to this vulnerability, links to original references, and the details of the exploit. It's important to ensure your browser is updated to protect your system from such vulnerabilities.

Exploit Details

A use-after-free vulnerability refers to a situation where an attacker can use a pointer to a memory location after it has been freed. This can lead to various attacks, including heap corruption and data breaches. In this case, the vulnerability affects the Cart in Google Chrome prior to 109..5414.74.

To exploit this vulnerability, an attacker needs to convince a user to install a malicious extension. Through this malicious extension, the attacker can potentially corrupt the heap memory via database corruption and a carefully crafted HTML page.

The vulnerability has been assigned a medium severity rating within Chromium's security ratings, making it a significant threat that users should be cautious about and, as always, only install extensions from trustworthy sources.

The following code snippet displays the use-after-free vulnerability in Google Chrome's Cart

// Vulnerable function in Chrome's Cart
function addToCart(item) {
  let cartItem = {id: item.id, name: item.name, price: item.price};
  let dbTransaction = database.transaction(["cart"], "readwrite");
  let cartStore = dbTransaction.objectStore("cart");
  
  // Add item to cart
  let request = cartStore.add(cartItem);
  
  // Vulnerable point in the code
  cartItem = null; // free the memory, but still in use.
}

The vulnerability exists in the addToCart() function where the cartItem object is freed (nullified) while it still remains in use by the request object added to the database.

For more details about this vulnerability, you can refer to the following sources

1. Google Chrome Releases Blog - Stable Channel Update for Desktop
2. Chromium Bug Tracker - Use-after-free in Cart
3. NVD - CVE-2023-0134

Mitigation and Remediation

To address this vulnerability and reduce any potential harm, Google Chrome users should update their browser to version 109..5414.74 or later. In doing so, your browser will receive essential patches and updates that mitigate the risk associated with the CVE-2023-0134 vulnerability. Always make sure to keep your browser and all installed extensions updated to their latest stable versions.

Furthermore, users should exercise caution while installing extensions, particularly those from untrusted sources. Remember that unsafe extensions can potentially access sensitive data and compromise the security of your system.

Conclusion

The CVE-2023-0134 vulnerability highlights the importance of being cautious while installing extensions and, primarily, underscores the need to keep your browser updated. Ensuring you're running the latest version of Google Chrome, having knowledge of potential vulnerabilities, and practicing safe browsing habits will collectively go a long way in keeping your system secure.

Timeline

Published on: 01/10/2023 20:15:00 UTC
Last modified on: 01/13/2023 14:06:00 UTC