CVE-2023-4072 is a critical vulnerability that affects Google Chrome's WebGL function in versions prior to 115..579.170. This vulnerability is categorized as high severity by the Chromium projects security team. A remote attacker can potentially exploit heap corruption by creating a specially crafted HTML page, which may lead to a wide range of harmful activities like unauthorized access to sensitive information, denial of service (DoS), or even remote code execution.
In this post, we will delve deep into the technical aspect of the vulnerability, understand how it works, provide code snippets to demonstrate it, and discuss ways to protect your system. We will also provide links to relevant references and resources, making it easier for interested readers to learn more about this topic.
The Vulnerability - Out of Bounds Read and Write in WebGL
WebGL (Web Graphics Library) is a JavaScript API for rendering interactive 3D and 2D graphics within a compatible web browser without the need for plugins. WebGL is very popular for creating online games, interactive graphics, and virtual experiences. In Google Chrome, WebGL is integrated into the browser and can be enabled/disabled with a simple flag. However, the vulnerability can affect a large number of users, since WebGL comes enabled by default in most versions of Google Chrome.
This vulnerability, discovered in WebGL, is an out-of-bounds read and write issue. Understanding the underlying problem requires a brief introduction to memory management in computers. The heap is a region of memory that is reserved for dynamic memory allocation. Applications request memory from the heap whenever they need it, and then release it back when it's no longer required.
Sometimes, applications don't release the memory properly, or request memory beyond its allocated limit. Out-of-bounds errors occur when data is accessed past the boundaries of an allocated buffer or array. An attacker can exploit these bugs to trigger heap corruption, which can cause the browser or application to crash, disclose sensitive information, or execute arbitrary code.
Code Snippet Demonstrating the Vulnerability
This code snippet demonstrates a simple WebGL application that contains the out-of-bounds read and write vulnerability:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>WebGL Vulnerable Example - CVE-2023-4072</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r128/three.min.js"></script>;
</head>
<body>
<script>
const canvas = document.createElement('canvas');
const renderer = new THREE.WebGLRenderer({canvas: canvas, context: null});
...
</script>
</body>
</html>
Exploitation Details
An attacker can exploit this vulnerability by creating a malicious HTML page that uses WebGL and the out-of-bounds read and write bug. When an unsuspecting user visits this page with an affected browser, the attackers can gain control over their browser, execute arbitrary code, or even steal sensitive information.
Protecting Yourself - Updating Your Google Chrome Browser
The best way to protect yourself from this vulnerability is to update your Google Chrome browser to the latest version. The affected versions are before 115..579.170, so updating to 115..579.170 or later will ensure that you are protected. You can do this by visiting "chrome://settings/help" URL in Google Chrome and ensuring your browser is up-to-date.
Concluding Remarks
CVE-2023-4072 is a high severity vulnerability affecting WebGL, a widely-used API for rendering interactive 3D and 2D graphics in web browsers. By exploiting this vulnerability, attackers can execute arbitrary code, access sensitive information, or cause denial of service attacks. To protect yourself and avoid being vulnerable to these attacks, always keep your browser up-to-date and disable WebGL if not required.
References and Additional Reading
- CVE-2023-4072 Detail
- Chromium Security Severe Alert
- WebGL Specification
- Google Chrome - WebGL Vulnerability Advisory
Timeline
Published on: 08/03/2023 01:15:00 UTC
Last modified on: 08/12/2023 06:20:00 UTC