The recent vulnerability discovered in Google Chrome versions prior to 116..5845.110, known as CVE-2023-4429, poses a high security risk for users of this popular web browser. This use-after-free issue in the Chrome Loader component allows a remote attacker to potentially exploit heap corruption via a maliciously crafted HTML page. As a result, it is critical that users familiarize themselves with the details of this vulnerability and take immediate steps to mitigate its potential effects. This post will provide a deep dive into the CVE-2023-4429 exploit by highlighting code snippets, revealing how to successfully craft a malicious HTML page, and examining ways to protect your Google Chrome browser from this critical vulnerability.

I. Code Snippet and Exploit Analysis

The use-after-free issue in the Chrome Loader stems from the inadvertent use of a pointer after the associated resource has been freed. This can lead to heap corruption and open the door for an attacker to gain unauthorized access or control over the affected system. The code snippet below illustrates the problematic sequence of events:

void Loader::processRequest() {
  // ...
  loaderClient()->didFinishLoading(timeFinishLoading); // [a]
  // ...

void Loader::processResponse(const WebURLResponse& response) {
  // ...
  if (response.isMultipart()) {
    // ...
    delete this; // [b]
    return; // [c]
  // ...

Immediately after, the Loader instance pointer is returned (marked as [c]).

4. The call stack unwinds back to Loader::processRequest, and the now-invalid instance pointer accesses loaderClient()->didFinishLoading (marked as [a]).

By achieving this heap corruption, an attacker can execute arbitrary code remotely.

II. Crafting a Malicious HTML Page

In order to exploit this vulnerability, an attacker can craft a malicious HTML page and lure unsuspecting users into accessing it. Once a user visits the compromised web page, the attacker can leverage the heap corruption exploit to gain control over the affected system. The link below provides a detailed example of a crafted HTML page that exploits the use-after-free vulnerability in the Chrome Loader:


Please exercise extreme caution when handling the linked example, as it contains actual exploitation code. It is intended for educational purposes only and should not be used for malicious intent.

III. Protecting Your Google Chrome Browser

To mitigate the effects of CVE-2023-4429, the optimal solution is to update your Google Chrome browser to version 116..5845.110 or later. Google has issued a patch for this critical vulnerability and recommends that all users upgrade immediately. To confirm your Chrome version and update if necessary, follow these simple steps:


CVE-2023-4429 represents a significant security threat to users of Google Chrome versions prior to 116..5845.110. By understanding this vulnerability's exploitation details, code snippets, and required mitigation steps, users can better protect themselves against potential attacks. Always remain vigilant and cautious when browsing the web and ensure that your Google Chrome browser is up-to-date with the latest security patches.


Published on: 08/23/2023 00:15:00 UTC
Last modified on: 08/26/2023 16:15:00 UTC