CVE-2023-3215 - Remote Heap Corruption Exploit in WebRTC via Use After Free Vulnerability in Google Chrome

In a recent Chromium security bulletin, a high severity vulnerability has been identified in Google Chrome prior to version 114..5735.133. The vulnerability, designated as CVE-2023-3215, could allow a remote attacker to exploit heap corruptions in the WebRTC module of Chrome through a crafted HTML page. This post will discuss the details about this vulnerability, its potential impact, available patches, and recommended security practices.

Overview

The vulnerability CVE-2023-3215 is a use after free (UAF) issue found in the WebRTC module of Google Chrome. WebRTC is a widely used open-source project that provides browsers and mobile applications with real-time communication (RTC) capabilities via simple APIs. It enables audio, video, and data streaming between peers without requiring plugins or external applications.

The affected Chrome versions suffer from a heap corruption vulnerability when an attacker can manipulate a crafted HTML page to dereference a pointer that has already been freed. This can lead to unpredictable memory corruption, remote code execution (RCE), and potentially complete control of the application or affected system.

A simple Pseudocode snippet that exhibits the issue can be found below

void WebRTCVulnerability() {
    Pointer *ptr = (Pointer *) malloc(size);
    // ...
    free(ptr); // The pointer is freed
    // ...
    ptr->call(); // Use after free vulnerability, using a pointer that was already freed
}

The above code snippet demonstrates how the use after free vulnerability can occur. By allowing the pointer ‘ptr’ to be used after it has already been freed, the application can potentially lead to heap corruption and remote code execution.

For complete details about this vulnerability, refer to the following official sources

1. Chromium Security Bulletin - High CVE-2023-3215
2. Google Chrome Release Blog - Stable Channel Update for Desktop
3. WebRTC Security Advisory - Vulnerability in Heap Memory Handling

Exploit Steps

A remote attacker could create a crafted HTML page to exploit this vulnerability and gain control over the affected Chrome browser or, in some cases, the system itself. The steps involved could be as follows:

1. The attacker creates a specially crafted HTML page that takes advantage of the use after free vulnerability in WebRTC.
2. The attacker then shares the crafted page with unsuspecting users via email, instant messaging, or social media.
3. A user opens the crafted page in their vulnerable version of Chrome, allowing the attacker to exploit heap corruption.
4. The attacker potentially gains control of the affected user's Chrome browser or, in extreme cases, their system.

Patch & Mitigation

Google has released an updated version of Chrome that patches this vulnerability. Users are strongly advised to update their Chrome browsers to version 114..5735.133 or later to protect themselves from this issue.

Select "Help" -> "About Google Chrome"

4. The browser will automatically check for updates, and if there's an available update, it will prompt you to install it.

In addition to applying the patch, users and companies should emphasize security awareness and encourage their users to practice safe browsing habits. Users should be wary of clicking on untrusted links, downloading suspicious files, and visiting unfamiliar websites.

Conclusion

In summary, the CVE-2023-3215 vulnerability poses a significant risk to users of Google Chrome prior to version 114..5735.133. It allows remote attackers to exploit heap corruption and potentially gain control of the affected Chrome browser or system. Users should update their browsers and remain vigilant to avoid falling victim to this vulnerability.

Timeline

Published on: 06/13/2023 18:15:00 UTC
Last modified on: 06/27/2023 02:15:00 UTC