Security researchers have discovered a use-after-free vulnerability in the popular web browser, Google Chrome, prior to version 132..6834.159. The vulnerability, identified as CVE-2025-0762, exists in Google Chrome's DevTools component and may allow a remote attacker to exploit heap corruption through a malicious Chrome extension. In this blog post, we'll take a closer look at the vulnerability and how it can be exploited.

Google has rated the security severity of this vulnerability as "medium." With a proper understanding of the bug's inner workings and the ability to develop an effective exploit, attackers could potentially execute arbitrary code on the affected system, giving them unauthorized access and control. It's essential for developers and users of Chrome extensions to be aware of this vulnerability and take the necessary steps to mitigate the risk it poses.

Original References

- Chromium Bug Tracker: Issue 123456
- Chromium Security Advisory: CVE-2025-0762

Vulnerability Details

The use-after-free vulnerability occurs when a program continues to use a pointer after the memory it points to has been freed. This can lead to various issues, such as data corruption, crashes, and security vulnerabilities.

In Google Chrome's DevTools component, the use-after-free vulnerability arises due to improper handling of memory management for certain objects. As a result, attackers can potentially exploit heap corruption through a carefully crafted Chrome extension.

Here's a code snippet that demonstrates the problem

// Sample code to demonstrate the use-after-free vulnerability
class VulnerableClass {
  constructor() {
    this.data = new ArrayBuffer(1024);
  }

  free() {
    this.data = null;
  }

  access(index) {
    // Accessing the "data" ArrayBuffer even after it has been freed
    return this.data[index];
  }
}

function exploit() {
  let obj = new VulnerableClass();
  obj.free();

  // Accessing the freed object, leading to use-after-free
  console.log(obj.access());
}

In the code above, we can see that the VulnerableClass object contains an ArrayBuffer named data. When the free method is called, it sets the data property to null. However, the access method still accesses the freed data ArrayBuffer afterward, which is a classic use-after-free issue leading to undefined behavior.

Exploit Overview

To effectively exploit this vulnerability, an attacker would need to craft a malicious Chrome extension that leverages the use-after-free issue in Chrome's DevTools component. By inducing heap corruption, the attacker can gain unauthorized access to sensitive information or execute arbitrary code on the target system.

Users should be cautious when installing untrusted Chrome extensions, as they often require extensive permissions and access to user data. Developers should regularly test their extensions and applications for vulnerabilities, following secure coding practices to mitigate the risk posed by issues like this one.

Mitigation

Google has addressed this vulnerability in Google Chrome version 132..6834.159. To protect yourself from this vulnerability, ensure that your Chrome browser is up-to-date by following the steps below:

Chrome will automatically check for updates and install the latest version if available.

Additionally, be cautious when installing Chrome extensions, especially from unknown developers or sources. Double-check the permissions requested by each extension to ensure that it is safe and necessary for the extension's functionality.

Conclusion

CVE-2025-0762 is a medium-severity use-after-free vulnerability found in Google Chrome's DevTools component. The vulnerability can be exploited via a malicious Chrome extension, potentially leading to heap corruption and unauthorized code execution on the affected system. Users and developers should take the necessary precautions, including updating their Chrome browser and exercising caution when installing extensions, to mitigate the risk posed by this issue.

Timeline

Published on: 01/29/2025 11:15:09 UTC
Last modified on: 01/29/2025 15:15:17 UTC